Document ID: EPA-HQ-OAR-2009-0443-0317
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2010-11-03T04:00Z

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Template for Technical Support Document

Definition of important terms used in this document:

1) Designated “unclassifiable” – an area where EPA could not
determine if there was a violation of the 2008 Lead NAAQS or a
contribution to a violation in a nearby area, because there was
insufficient air quality data for both 2006-2008 and 2007-2009 and where
additional monitoring data for 2010 could not result in a different
designation.

2) Designated “attainment” – an area which EPA has determined,
based on the most recent 3 years of certified air quality data from
2006-2008 or 2007-2009, has no violations of the 2008 Lead NAAQS during
36 consecutive valid 3-month site means; and which EPA has further
determined does not contribute to a violation of the 2008 Lead NAAQS in
a nearby area and that additional monitoring data from 2010 could not
result in a different designation.

3) Designated nonattainment area – an area which EPA has determined,
based on a State recommendation and/or on the technical analysis
included in this document, has a violation of the 2008 Lead NAAQS during
the most recent three consecutive years of quality-assured, certified
air quality data.  

4) Prior nonattainment area – an area that is currently designated as
nonattainment or maintenance for the 1978 Lead Standard (including both
current nonattainment areas and maintenance areas).

5) Recommended nonattainment area – an area a State or Tribe has
recommended to EPA be designated as nonattainment.

6) Violating monitor – an ambient air monitor whose design value
exceeds 0.15 micrograms per cubic meter (ug/m3). As described in
Appendix R of part 50, a violation can be based on either Pb-TSP or 
Pb-PM10 data and only three months of data are necessary to produce a
valid violating design value. 

7) 1978 Lead NAAQS – 1.5 µg/m3, National Ambient Air Quality Standard
for lead promulgated in 1978.  Based on Pb-TSP indicator and averaged
over a calendar quarter.

8) 2008 Lead NAAQS -  0.15 µg/m3,  National Ambient Air Quality
Standard for lead promulgated in 2008.  Based on Pb-TSP indicator and a
three-month rolling average.  Pb-PM10 data may be used in limited
instances, including to show nonattainment. 

Texas

Area Designations For the 

2008 Lead National Ambient Air Quality Standards

EPA has revised the level of the primary (health-based) standard from
1.5 micrograms per cubic meter (μg/m³) to 0.15 μg/m³ measured as
total suspended particles (TSP).  EPA has revised the secondary
(welfare-based) standard to be identical in all respects to the primary
standard.

Pursuant to section 107(d) of the Clean Air Act, EPA must designate as
“nonattainment” those areas that violate the NAAQS and those nearby
areas that contribute to violations.  The table below identifies the
counties or portions of counties (or tribal areas) in Texas that EPA is
designating “nonattainment” for the 2008 lead national ambient air
quality standard (2008 Lead NAAQS).  

Table 1

Area (listed alphabetically)	[Texas] Recommended Nonattainment Counties
EPA’s Designated Nonattainment Counties	Nonattainment area for 1978
Lead NAAQS

Frisco	Collin County (partial) 	Collin County (partial)	Collin County
(partial)

Technical analysis for Frisco

Introduction  

This technical analysis for Frisco, Texas area identifies the partial
county with a monitor(s) that violates the 2008 Lead NAAQS and evaluates
nearby counties for contributions to lead concentrations in the area. 
EPA has evaluated these counties based on the weight of evidence of the
following factors recommended in previous EPA guidance:  

Air quality in potentially included versus excluded areas;

Emissions and emissions-related data in areas potentially included
versus excluded from the nonattainment area, including population data,
growth rates and patterns and emissions controls;

Meteorology (weather/transport patterns);

Geography/topography (mountain ranges or other air basin boundaries);

Jurisdictional boundaries (e.g., counties, air districts, reservations,
etc.); and

Any other relevant information submitted to or collected by EPA (e.g.,
modeling where done appropriately).

Figure 1 is a map of the area analyzed showing the locations and design
values of air quality monitors in the area, and the counties surrounding
any violating air quality monitors (Exide facility was previously called
GNB).

Figure 1: Frisco, Texas recommended nonattainment 

For this area, EPA previously established lead nonattainment boundaries
for the 1978 Lead NAAQS that included a portion of Collin County located
in Texas.  For each revision to a NAAQS EPA is required to conduct a
separate designation action, which may result in the same or a different
nonattainment boundary.

In October 2009, Texas recommended that a portion of Collin County be
designated as  “nonattainment” for the 2008 Lead NAAQS based on air
quality data from 2006-2008.  Their recommendation was based on data
from (a) Federal Reference Method (FRM) or Federal Equivalent Method
(FEM) monitor(s) located in the state.  Texas’ recommendation was
submitted in a letter from Governor Rick Perry, and dated October 14,
2009.  In October 2010, Exide submitted a permit alteration request to
TCEQ documenting a reduction in permitted maximum allowable emission
rates for some sources.  On October 6, 2010 TCEQ issued a permit
alteration to the facility revising the permitted maximum allowable
emission rates.  TCEQ performed dispersion modeling to address those
emission reductions in order to determine a revised boundary of the
nonattainment area.  On October 13, 2010, the Governor of Texas
submitted a revised lead nonattainment area boundary recommendation to
EPA based on TCEQ modeling that incorporated the reduced permit
allowable limits, reducing the size of the nonattainment area.    

Based on EPA's technical analysis described below, EPA is designating a
portion of Collin County, Texas as nonattainment for the 2008 Lead NAAQS
based upon currently available information.  This county is listed above
in Table 1.

Detailed Assessment

Air Quality Data 

This factor considers the Lead design values (in µg/m3) for air quality
monitors in Collin County in the Frisco area as well as the surrounding
area based on data for the 2006-2008 period.  A monitor’s design value
indicates whether that monitor attains a specified air quality standard.
The 2008 Lead NAAQS are met at a monitoring site when the identified
design value is valid and less than or equal to 0.15 µg/m3.  A design
value is only valid if minimum data completeness criteria are met.  A
Lead design value that meets the NAAQS is generally considered valid if
it encompasses 36 consecutive valid 3-month site means (specifically for
a 3-year calendar period and the two previous months).  For this
purpose, a 3-month site mean is valid if valid data were obtained for at
least 75 percent of the scheduled monitoring days in the 3-month period.
 A Lead design value that does not meet the NAAQS is considered valid if
at least one 3-month mean that meets the same 75 percent requirement is
above the NAAQS.  That is, a site does not have to monitor for three
full calendar years in order to have a valid violating design value; a
site could monitor just three months and still produce a valid
(violating) design value.

The 2008 Lead NAAQS design values for Collin County in Frisco and
surrounding area are shown in Table 2. 

Table 2.  Air Quality Data 

 

County	State 

Recommended

 Nonattainment?	Monitor Name	Monitor Air Quality 

System ID	Monitor Location	Lead Design 

Value, 

2006 - 2008

(µg/m3)	Lead Design

Value

2007-2009

(µg/m3)

Collin County, Texas	Yes 	5th St.	48-085-0003	W. 5th St.	0.28	0.33

Ash St.	48-085-0007	6931 Ash St.	0.17	0.17

N. property	48-085-0009	Next to north property line on facility property
1.26*	1.26*

*Monitor in Bold has the highest design value in the respective county.
As discussed in the response to comments, this monitor has been listed
as a SLAMS monitor and the data has been reported by the State as
ambient data for the last three years.  EPA understands that Texas now
believes the data from this monitor should be designated as
non-regulatory data.   This issue will be addressed through future
discussions with the State. As noted by TCEQ, there are two other
monitors in the area that have recorded measurements above the NAAQS for
lead. So even if the data from 480850009 were not considered, a
nonattainment designation would still be appropriate. 

Collin County shows a violation of the 2008 Lead NAAQS.  Therefore some
area in this county and possibly additional areas in surrounding
counties must be designated nonattainment.  The absence of a violating
monitor alone is not a sufficient reason to eliminate nearby counties as
candidates for nonattainment status.  The Act calls for areas which
measure nonattainment and areas that contribute to nonattainment be
designated nonattainment.  Each area must be evaluated based on the
weight of evidence of the eight factors and other relevant information. 

Currently, there are no nearby emissions sources, other than Exide, that
may be contributing to the violating monitors. According to TCEQ, the
next largest point source of lead within 50 km of the Exide plant had a
2006 lead emissions of 0.03 tons per year (tpy), and the total lead
emissions from all sources (other than Exide) within 50 km from the
Exide plant was 0.0602 tpy. 

Emissions and Emissions-Related Data

Evidence of lead emissions sources surrounding a violating monitor are
an important factor for determining whether a nearby area is
contributing to a monitored violation.  For this factor, EPA evaluated
county level emission data for lead and population data.

Emissions 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 2, which is the most up-to-date version of the national
inventory available when these data were compiled for the designations
process in 2009.  See   HYPERLINK
"http://www.epa.gov/ttnchie1/net/2005inventory.html" 
http://www.epa.gov/ttnchie1/net/2005inventory.html .  EPA recognizes
that for certain counties, emissions may have changed since 2005.  For
example, certain large sources of emissions in or near this area may
have installed emission controls or otherwise significantly reduced
emissions since 2005.  Some States provided updated information on
emissions and emission controls in their comments to EPA.  Texas
provided updated emissions information based on the 2007 state emission
inventory (EI). The 2007 EI shows only two stationary sources in Collin
County reporting lead emissions: Exide and Encore Wire Limited, which is
located in McKinney, Texas, approximately 12 miles from Exide. Based on
the 2007 EI data, Exide accounts for approximately 98.6 percent of
stationary source lead emissions in Collin County. Because of its
significant distance from the Exide site and its small reported lead
emission, Encore Wire Limited would not contribute to lead
concentrations near Exide. The data is provided in Table 3.

There are approximately 20,000 airport facilities in the U.S. at which
leaded aviation gasoline is consumed.  To evaluate the potential impact
of emissions at and near these facilities, EPA recommends that States
use the draft 2008 NEI data for airport facilities in Collin County
which use leaded aviation gasoline. Collin County airports are included
in Table 4. 

 

Table 3 shows total emissions of lead (given in tpy) for violating and
potentially contributing counties in and around the Frisco area. There
are no point sources emitting (or anticipated to contribute) greater
than 0.1 ton per year of lead according to the 2007 state emissions
inventory. The county that is part of the Frisco nonattainment area for
the 2008 Lead NAAQS is shown in boldface.  

Table 3.  Lead Emissions

 

County	Facility in State Recommended Nonattainment Area?	Facility Name 
Facility Location	Total  Lead Emissions  (tpy) 

2007 State Emission Inventory 

Collin County, Texas	Yes  (a portion)	Exide Corporation	7471 S. 5th St.,
Frisco, TX	2.0

Collin County, Texas	No	Encore Wire Corporation	1410 Millwood, McKinny,
TX 	0.03

Figure 2: Aerial view of Exide Technologies facility and surrounding
area

The monitors with site numbers (in red) are the currently existing
monitors

 

Table 4. Airport facilities using leaded aviation gas in Collin County

City

	Facility Name	Type	Pb (tpy)	Distance to NA area (km)

MC KINNEY	COLLIN COUNTY RGNL AT MC KINNEY	AIRPORT	0.294125	21.5

CELINA	FOUR WINDS	AIRPORT	0.058211	24

WESTMINSTER	FLYING T RANCH	AIRPORT	0.058211	42.2

DALLAS	AIR PARK-DALLAS	AIRPORT	0.056668	11.5

MCKINNEY	AERO COUNTRY	AIRPORT	0.025000	9.2

FARMERSVILLE	MULLINS LANDING	AIRPORT	0.017764	40.5

MC KINNEY	SQUARE AIR	AIRPORT	0.016636	25.75

PRINCETON	JSI	AIRPORT	0.016636	31.1

FARMERSVILLE	SHORT STOP	AIRPORT	0.014379	46.5

CELINA	TALLOWS FIELD	AIRPORT	0.013251	17.5

WESTMINSTER	BAYLIE	AIRPORT	0.013251	40.5

ALLEN	KITTYHAWK	AIRPORT	0.009167	12.7

CELINA	CELINA FIELD	AIRPORT	0.008643	17.8

DALLAS	LAVON NORTH	AIRPORT	0.003417	28.8

CELINA	BISHOP'S LANDING	AIRPORT	0.001667	25.7

ALLEN	EDS	HELIPORT	0.000233	13.1

ALLEN/LUCAS	GMF RANCH	HELIPORT	0.000233	24

FRISCO	EDS SUPERDROME	HELIPORT	0.000233	2.9

LUCAS	AAF	HELIPORT	0.000233	21.8

MC KINNEY	LMC	HELIPORT	0.000233	18.6

PLANO	EDS ADMINISTRATION NR 1	HELIPORT	0.000233	6

PLANO	MCP	HELIPORT	0.000233	12.5

PLANO	E D S	HELIPORT	0.000233	6.2

PLANO	EDS HANGAR	HELIPORT	0.000233	6.7

PLANO	CHILDRENS/PRESBYTERIAN HEALTH CTR OF N TX	HELIPORT	0.000233	9.3

PRINCETON	AERO CRAFTER INC	HELIPORT	0.000233	27.8

PRINCETON	PECKS	HELIPORT	0.000233	34.8

RICHARDSON	OWENS COUNTRY SAUSAGE	HELIPORT	0.000233	19.4

WYLIE	PUTMAN	HELIPORT	0.000233	28.9

WYLIE	LADUE RANCH	HELIPORT	0.000233	32.1

WYLIE	WALDEN RANCH	HELIPORT	0.000233	31.7

Population Data

Table 5 shows the 2008 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  These data help assess the extent to which the concentration of
human activities in the area and concentration of population-oriented
commercial development may indicate emissions-based activity
contributing to elevated ambient lead levels.  This may include ambient
lead contributions from activities that would disturb lead that has been
deposited on the ground or on other surfaces.  Re-entrainment of
historically deposited lead is not reflected in the emissions inventory.

Table 5.  Population Data

County	State Recommended Nonattainment?	2008 Population	2008

Population Density (pop/sq mi)	Population Change 2000-2008	Population %
Change 2000-2008

Collin, Texas	Yes 	762,010

	860	261,812

	52

Source of data: U.S. Census Bureau estimates for 2008 (  HYPERLINK
"http://www.census.gov/popest/datasets.html" 
http://www.census.gov/popest/datasets.html ) and estimation of the area
of U.S. Counties]

Growth Rates and Patterns  

Collin County shows a population change of fifty two percent between
2000 and 2008, which has been considered when determining the
nonattainment status of the County.  However, since there are no
additional sources of lead emissions in Collin County to be considered,
the population growth in the area should not be a factor in determining
the boundary for the area. 

EPA has considered the population growth rate for this area and does not
believe that it affects the boundary recommendation.

Emissions Controls

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 2 represent emissions levels
taking into account any control strategies implemented in Frisco before
2005 on stationary sources. As noted above, Exide applied for a received
a revised permit that lowered the allowed emissions rates for the
facility.. The area was designated to attainment of the 1978 lead NAAQS
and has been under the control of a 10-year maintenance plan since 1999.
TCEQ submitted a second 10 year maintenance plan to EPA on September 15,
2009 in order to demonstrate a continued attainment of the 1978
standard, until a SIP revision for the nonattainment area is approved by
EPA.   

Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2006-2009 are in Figure 3 below. 
These data may provide evidence of the potential for lead emissions
sources located upwind of a violating monitor to contribute to ambient
lead levels at the violation location.  For each county, EPA reviewed
the prevailing wind direction and wind speed on days/months with the
highest observed ambient lead levels. A three-dimensional bar chart
shows the wind frequencies in eight directions, for the four seasons,
based on thirty two years of historical data for Frisco, Texas.  The
chart of frequencies reflects the directions from which the winds come. 
The area recommended by Texas reflects this pattern because the area
extends to the north further from the Exide facility than to the south
reflecting the prevailing south wind.  

   

 

Figure 3: Historic wind direction frequency in each of the four seasons
in Collin County, Texas

As shown in Figure 3, the prevailing surface winds predominantly were
from the SSW.  

Geography/topography (mountain ranges or other air basin boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of lead over the Frisco area.

The Frisco area does not have any geographical or topographical barriers
significantly limiting air-pollution transport within its air shed. 
Therefore, this factor did not play a significant role in determining
the nonattainment boundary.

Jurisdictional boundaries 

Existing jurisdictional boundaries may be helpful in articulating a
boundary for purposes of nonattainment designations, and for purposes of
carrying out the governmental responsibilities of planning for
attainment of the lead NAAQS and implementing control measures.  These
existing boundaries may include an existing nonattainment or maintenance
area boundary, a county or township boundary, a metropolitan area
boundary, an air management district, or an urban planning boundary
established for coordinating business development or transportation
activities.

The nonattainment area is a portion of Collin County.  Surrounding
counties have no lead emitting sources, and thus do not contribute to
the nonattainment area in Collin County. TCEQ modeling shows that all
predicted NAAQS violations fall within Collin County.

Other Relevant Information

μg/m3 for a rolling three-month average. The location of the GLCmax is
the same as the location of monitor 480850009 on the north property line
of the Exide Technologies site.  Predicted concentrations exceeding the
NAAQS extended approximately 1.3 kilometers (km) to the north, 0.8 km to
the south, 0.8 km to the west, and 0.4 km to the east of the site
property line. 

In October 2010, TCEQ performed modeling using the new permitted
allowable emission rates (lb/hr) that were revised as part of the
October 6, 2010 permit alteration.  The revised modeling conducted by
TCEQ was completed using two receptor grids near the Exide facility –
one grid using 50-meter spacing and one grid using 100-meter spacing. 
The new model runs showed that the predicted maximum ground level
concentration (GLCmax) is 0.837 μg/m3 for a rolling three-month
average. The location of the GLCmax is the same as the location of
monitor 480850009 on the north property line of the Exide Technologies
site.  Predicted concentrations exceeding the NAAQS extended
approximately 0.8 kilometers (km) to the north, 0.5 km to the south, 0.5
km to the west, and 0.2 km to the east of the site property line. 

EPA completed a review of the revised October 2010 modeling performed by
TCEQ and confirmed that the modeled emission rates matched the revised
permit allowables contained in Exide’s permit dated October 6, 2010. 
For all sources, except the vehicle traffic fugitive emissions (EPNs 41,
42, and 43), the hourly emissions permit limit was included in the
modeling conducted by TCEQ.  The modeled emission rates included for the
vehicle traffic emission points were based on the annual emissions
permit limit converted to a short term emission rate assuming continuous
operation (i.e. 8,760 hours per year).  For fugitive sources that are
listed in a “group” with a combined permit allowable within the
current permit (i.e., 10 and 35; 41, 42, and 43) the total permitted
emissions limit was modeled from each of the emission points within the
grouped listing.  Therefore, the modeling conducted by TCEQ accounted
for the total permitted emissions for the group coming from each modeled
EPN at all times.  The modeled emission rates included by TCEQ in the
October 2010 modeling appear to be appropriate, since these emission
rates are consistent with the permit allowables for the modeled emission
sources.

In addition to reviewing the revised modeled emission rates, EPA also
reran the model runs using both the 50- and 100-m receptor grids to
confirm the model outputs provided by TCEQ.  EPA post processed the
model outputs using the LeadPost post processer to calculate the rolling
three-month average concentrations for each receptor included in the
modeling.  The results from the EPA’s post processing confirmed the
modeling results provided by TCEQ.  

All predicted concentrations greater than the NAAQS are located within
Collin County.  Figure 5 shows the lead concentrations in the
recommended non attainment area.

	

Figure 5: Recommended nonattainment area with modeling results.

During discussions with Exide in October 2010 regarding the revised
modeling conducted by TCEQ, Exide raised questions regarding the
approach used to model the total fugitive “group” permit allowables
from each individual emission point (EPNs 10 and 35, and 41, 42, and
43).  Exide’s consultant also suggested that the modeling was
conservative because Texas does not usually include haul road (lead
re-entrained from traffic on Exide’s facility) emissions in minor
source permits.

EPA has reviewed the issue raised about the Furnace Fugitive Emissions
(emission points 10 and 35).  Exide utilized updated AP-42 emission
factors to quantify these emission points and lower the permitted
emission limit from 0.27 lb/hr to 0.08 lb/hr.  The AP-42 emission factor
has an E rating, which is the lowest confidence level rating of AP-42
factors.  The emission factor also has a range of variability from 0.2
to 0.6 lb/ton of metal processed.  Exide chose 0.4 lb/ton as the basis
for the emission calculation with a 98% hood capture efficiency and a
10.5 ton per hour maximum metal throughput.  This calculates to a
maximum emission limit of 0.08 lb/hr.   TCEQ modeled this new 0.08 lb/hr
allowable for each of the release points in the modeling.  Given the
range of the emission calculation, the lack of testing or site specific
data to support Exide's selection, the fact that the new emission limit
is approximately 30% of the previous emission limit and the fact that
Exide did not quantify how much emissions would be coming out of each
emission point, TCEQ's modeling of these sources seems reasonable.

EPA also reviewed the three area sources (emission points 41, 42, 43). 
The permitted annual emission rate for these 3 sources combined is 0.17
tons of Pb.  This rate was assumed to be constant for daily and hourly
emissions for modeling purposes. Work day variations could result in
larger daily or hourly emissions so assigning the rate to each is
conservative but understandable.  EPA does not agree with Exide’s
consultant that the haul road/traffic emissions should not have been
included in the modeling.  The haul road emissions have permit limits
and, under federal permitting guidance for PSD, these sources should be
included in modeling and permitting.  Moreover, EPA is required to
designate areas where ambient air quality does not meet the NAAQS,
regardless of whether such ambient concentrations are due to
re-entrainment of previously-emitted Pb, or to more recent emissions
from a nearby stationary source.

Exide indicated to EPA that it considers TCEQ’s modeling to be overly
conservative because including emissions from EPNs 10 and 35, and 41,
42, and 43 amounts to “double counting”  certain lead emissions.  To
address the question of whether these emissions (which amount to less
than 10% of the facility’s total emissions) would drastically change
the potential boundary (if any one EPN were under-estimated or
over-estimated), EPA completed additional model sensitivity runs to
examine how the boundary and receptors with predicted concentrations
greater than the NAAQS would be impacted if the total emissions were
modeled through either EPN 10 or 35, and one of the other individual
emission sources (EPNs 41, 42, or 43).  Three additional modeling runs
were conducted as part of this analysis using the 50-meter grid spacing:

MIN_S: This model run included all sources except EPNs 10, 41, and 43. 
The total permit allowables from the Furnace Fugitives were modeled from
EPN 35.  The total permit allowables from the Vehicle Traffic were
modeled from EPN 42.

MIN_W: This model run included all sources except EPNs 35, 42, and 43. 
The total permit allowables from the Furnace Fugitives were modeled from
EPN 10.  The total permit allowables from the Vehicle Traffic were
modeled from EPN 41.

MIN_E: This model run included all sources except EPNs 35, 41, and 42. 
The total permit allowables from the Furnace Fugitives were modeled from
EPN 10.  The total permit allowables from the Vehicle Traffic were
modeled from EPN 43.

EPA post processed the results from these model runs and created plots
showing the predicted three-month average concentrations.  Figure 6
shows the results of EPA’s modeling with a 50 m receptor grid that
confirms the modeling that TCEQ performed.  Figures 7, 8, and 9 show the
lead concentrations for these three model runs along with the boundary
of the nonattainment area proposed by TCEQ.  



Figure 6: Recommended nonattainment area from TCEQ based on EPA’s
modeling (50 m).

Figure 7: Recommended nonattainment area with modeling results from
MIN_S model run.

Figure 8: Recommended nonattainment area with modeling results from
MIN_W model run.

Figure 9: Recommended nonattainment area with modeling results from
MIN_E model run.

As shown in these figures, the difference in the boundary for predicted
concentrations greater than the NAAQS when the total emissions were
modeled through just one of the individual fugitive sources was at most
50 to 100 meters.  These alternate runs confirm that even if TCEQ
refined their modeling approach to address Exide’s concerns of
potential “double-counting” of emission rates, the new inputs would
result only in minor differences in the boundary of the area having
predicted lead concentrations greater than the NAAQS.  To be clear, EPA
does not consider TCEQ’s analysis to be overly conservative and does
not agree with Exide’s comments.  EPA considers the modeling approach
utilized by TCEQ to determine the recommended nonattainment area to be
reasonable and appropriate. 

Conclusion

After considering the factors described above, EPA has determined that
it is appropriate to designate the portion of Collin County recommended
by Texas listed in Table 1 as a nonattainment area for the 2008 Lead
NAAQS.  The nonattainment area encompasses the area immediately
surrounding the Exide Technologies battery recycling plant in Frisco,
bounded to the north by latitude 33.153, to the east by longitude
-96.822, to the south by latitude 33.131, and to the west by longitude
-96.837.  This portion of the county encompasses the area projected by
the modeling to be above the standard.  In addition, air quality
monitors in the nonattainment area show violations of the 2008 Lead
NAAQS, based on 2006-2008 and 2007-2009 air quality data.  

Based on its consideration of all the relevant, available information,
as described above, EPA believes that the boundaries described herein
encompass the entire area that does not meet the 2008 Pb NAAQS.

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 .  Since Exide could operate at their short-term rates for an extended
time and the Pb NAAQS is less than an annual standard, TCEQ and EPA both
modeled short-term (lb/hr) emission limits in this modeling.  EPA notes
that recent actual annual emissions have been below the revised
permitted annual allowable emission limits.  

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