subject to the MACT. The 1999 MACT rule established a plant-wide lead
emission limit of 1 lb of lead per ton of lead produced that applies to
the aggregation of emissions from specific sources that discharge from
air pollution control devices. Compliance with the plant-wide emission
limit is demonstrated by annual stack testing. The rule lists nine
sources as subject to the plant-wide limit including: (1) Sinter
machine, (2) blast furnace, (3) dross furnace, (4) dross furnace
charging location, (5) blast furnace and dross furnace tapping
location, (6) sinter machine charging location, (7) sinter machine
discharge end, (8) sinter crushing and sizing equipment, and (9) sinter
machine area. At the Doe Run plant, lead emissions from these sources
are controlled by baghouses that exhaust through two stacks. The
sources in the sinter operation, the blast furnace, and the dross
furnace are controlled by three baghouses all of which discharge
through one emission point, which is designated as the main stack. The
building that houses the blast furnace and dross kettles is vented to a
separate baghouse (7) which discharges through a separate
stack, designated as the furnace area stack.
    Under the 1999 MACT rule, all other sources of process fugitive and
fugitive dust emissions are required to follow work practice standards
detailed in the plant's standard operating procedures (SOP) manual.
    The HAP emitted in the largest quantities from the Doe Run facility
are

lead compounds, which account for over 99 percent of the total HAP
emissions by mass. The remaining HAP emissions are arsenic, antimony,
cadmium, cobalt, nickel and trace organic HAP. Negligible levels of
organic HAP are also emitted from natural gas-fired space heating at
the facility and the incomplete combustion of coke in the blast
furnace. Further discussions of the emission profile for this facility
is included in the Technical Support Document in the docket.
3. Missouri SIP and the Lead NAAQS as They Apply to Doe Run Company,
Herculaneum, Missouri
    In addition to the MACT standard, the Doe Run Company's primary
lead smelter in Herculaneum, Missouri is subject to a SIP for the
purpose of attaining and maintaining the lead NAAQS.\17\ The current
SIP, which was approved in 2002, addresses the former lead ambient air
concentration limit of 1.5 [mu]g/m\3\ NAAQS. In addition, the 2007 SIP
submittal from the State includes requirements addressing lead
emissions from the Doe Run facility and can be found at http://www.dnr.mo.gov/env/apcp/docs/2009drh-leadsip.pdf.
---------------------------------------------------------------------------

    \17\ EPA most recently approved the Missouri SIP for Herculaneum
in 2002 (67 FR 18497, April 16, 2002). Missouri Department of
Natural Resources (MDNR) substantially revised the requirements for
the smelter in 2007. EPA has proposed approval of this revision, but
has not yet taken final action.
---------------------------------------------------------------------------

    In 2008, EPA revised the lead NAAQS from 1.5 [mu]g/m\3\ to 0.15
[mu]g/m\3\. In November 2010, EPA identified or ``designated'' several
areas as not meeting the lead NAAQS. These ``nonattainment''
designations include portions of Jefferson County, Missouri surrounding
the Doe Run facility. Missouri is required by the Act to take steps to
further control pollution in this area, and to detail these steps in a
revision to the SIP. The revised SIP is due to EPA within eighteen
months after the effective date of the designation, or by June 2012,
and attainment of the NAAQS should be achieved by 2016.
    The SIP and the pending 2007 SIP submittal contain specific
measures to be implemented by the Doe Run plant to reduce lead
emissions. The State of Missouri revised the control requirements for
the Doe Run facility in 2001 and 2007, requiring numerous emissions-
reducing measures and improvements to add-on control devices,
processes, and work practices.\18\ These included improvements to
existing emission control technology, adding or upgrading enclosures,
process changes and limitations, and work practices. These requirements
are summarized below.
---------------------------------------------------------------------------

    \18\ EPA most recently approved the Missouri SIP for Herculaneum
in 2002 (67 FR 18497, April 16, 2002). MDNR substantially revised
the requirements for the smelter in 2007. EPA has proposed approval
of this revision, but has not yet taken final action.
---------------------------------------------------------------------------

    Point Source Requirements--As required under the SIP, lead
emissions from the refining kettles and refining building emissions
must be captured and vented to baghouses. Doe Run implemented these
controls and vents the emissions to baghouses 8 and 9
and the exhaust from the baghouse 9 is combined with baghouse
7 exhaust and vented to a common stack. Although the MACT
standard does not require Doe Run to do so, it has included emissions
from refining Baghouses 8 and 9 in their
demonstrations of compliance with the MACT plant-wide lead emission
limit.
    Under the 2007 SIP submittal, Doe Run was required to make
improvements to existing baghouse controls including the installation
of pleated filters and lowering the air-to-cloth ratio for baghouses,
increased ventilation and improved ventilation hoods at the blast
furnace, and using reverse flow technology for baghouse cleaning. The
2007 SIP submittal also required the installation of enclosures and/or
partial enclosures for unloading ore concentrate, sinter storage, and
the sides of the sinter machine (which will be evacuated to a
baghouse).
    Process Requirements--Process changes to reduce emissions required
by the SIP included a process control system for the injection of air
through the blast furnace tuyeres located at the bottom of the blast
furnace, limitations on individual process and overall plant
throughputs, and limiting specific operations to only certain times of
the day when the impact on ambient air concentrations is less. The SIP
also stipulates that emissions from malfunctions will be reduced by
alarms that sound when the baghouse fan malfunctions, an interlock
system to restrict air flow into the blast furnace when the baghouse is
not operating properly, and cameras for the dross and refinery kettles
to detect kettle failure (i.e., when a plume of smoke is detected from
the stack, the kettle burner can be immediately shut off and the
problem corrected).
    Fugitive Dust Requirements--Under both the current SIP and the 2007
SIP submittal, work practices are required to reduce fugitive dust
emissions. Requirements include road watering and automatic sprinklers,
using new regenerative sweepers to remove dust from paved surfaces to
reduce emissions from traffic, maintaining a minimum water content
percentage for ore concentrate and for baghouse dust that is loaded
into railcars, and inspecting the siding that encloses buildings
(followed by prompt repairs if needed).
    Missouri requires Doe Run to report all metal HAP emissions
annually based on a speciation analysis that was performed.\19\ The
state also requires an annual emissions inventory based on the stack
tests for the point discharges and AP-42 or facility-specific emission
factors for fugitive emissions.
---------------------------------------------------------------------------

    \19\ Doe Run Company submits annual emissions inventories to
MDNR that report speciated metals using speciation factors for each
metal/source derived in the late 1990s through emissions testing.
---------------------------------------------------------------------------

    As a result of the implementation of the emission control
requirements in the currently approved 2002 SIP, and the additional
requirements adopted by the state, as discussed above, the Doe Run
facility has achieved a significant reduction of lead and metal HAP
emissions since 2000 through a combination of reduced production levels
and improved emissions controls. Based on emissions inventory data
submitted to the Missouri Department of Natural Resources (DNR), total
HAP emissions have been reduced from an estimated 140 tons in 2000 to
20 tons in 2008, and the majority of the 20 tons are lead compound
emissions. The 2008 reported emissions reflect implementation of all
emission controls stipulated in the 2002 SIP and the 2007 SIP revision.
4. Other Federal and State Actions Affecting Doe Run Company
    More recently, the 2008 revision to the lead NAAQS has resulted in
Doe Run Company deciding that it is not feasible for the facility to
reduce emissions further to the level necessary to meet the newly
revised NAAQS without closure of the current smelting operations. As a
result of past and ongoing regulatory compliance issues at the
facility, the facility has entered into a consent decree with U.S. EPA
Region VII and the State of Missouri. Under the consent decree, the
facility will, among other things, close the existing smelter operation
and remediate the site to an agreed-upon level. The consent decree
requires that all support operations for the smelter cease by December
31, 2013 and that the blast furnace cease operations by April 1, 2014.
Remediation of the site is required to commence following approval of a
plan to be submitted to EPA in January 2013. Under the consent decree,
the existing refining, casting and alloying operations

will be allowed to continue operation. Notice of the consent decree was
published for public comment on October 15, 2010, (75 FR 63506). Once
finalized, the consent decree is federally enforceable among the
parties.
    Prior to closure of the current smelter, the Doe Run Company may
build and bring to full operation a new hydrometallurgical process that
will produce lead from lead sulfide ore, potentially adjacent to the
current smelter. The hydrometallurgical process uses chemical reactions
involving fluboric acid which allows recovery of lead metal through
leaching, electrowinning, and co-product treatment processes. Some of
the lead from the new process is likely to undergo further processing
at the existing refinery, primarily for remelting/casting purposes.
Based on limited data from a demonstration project, Doe Run expects
that lead emissions from the hydrometallurgical process will be
minimal.

V. Analyses Results and Proposed Decisions

    This section of the preamble provides a description of the dataset
used in the RTR analysis, the results of our RTR for the source
category, and our proposed decisions concerning changes to the Primary
Lead Smelting MACT standard. As noted previously, all references to
lead emissions in this proposal means ``lead compounds,'' which is the
regulated HAP under CAA section 112. All reference to lead production
means the production of element lead.

A. What data were used in our risk analyses?

    For the Primary Lead Smelting source category, we compiled a
preliminary dataset using readily available information, reviewed the
data, and made changes where necessary. The preliminary dataset was
based on data in the 2002 National Emissions Inventory (NEI) Final
Inventory, Version 1 (made publicly available on February 26, 2006),
and the 2005 National Emissions Inventory (NEI), version 2.0 (made
publicly available in October 2008). The 2005 NEI was updated to
develop the 2005 National Air Toxics Assessment (NATA) Inventory. NATA
inventory updates for the primary lead smelting category included SIP
data provided by the state of MO to EPA. The 2005 NATA inventory was
used with updated 2008 data received in an Information Collection
Request (ICR) response from the Doe Run facility. The NEI is a database
that contains information about sources that emit criteria air
pollutants, their precursors, and HAP. The NEI database includes
estimates of annual air pollutant emissions from point and volume
sources, emission release characteristic data such as emission release
height, temperature, velocity, and location latitude/longitude
coordinates. We reviewed the NEI datasets, checked geographic
coordinates, and made changes based on available information. We also
reviewed the emissions and other data to identify data anomalies that
could affect risk estimates.
    The risk assessment was based on estimates of the actual emissions
and allowable emissions. The estimates of actual emissions were for the
year 2008 and were based on data from the ICR along with data from our
NEI dataset. These estimates included both stack and fugitive emission
sources. Fugitive dust sources include material handling (concentrate,
sinter, fume and dross), plantwide resuspension (roadways, storage
piles and plant yard) and other miscellaneous sources (vents and heat
stacks). The material handling sources contribute approximately 84
percent of the total fugitive dust emissions, while plantwide
resuspension and miscellaneous sources contribute approximately 11 and
5 percent, respectively. The estimates of allowable emissions were
calculated using production data from the ICR response combined with
the current emissions limits in the MACT standard.
    Lead compounds account for about 99 percent of the HAP emissions
from the source category, or about 20 tons in 2008. The facility also
reported small emissions of five other metal HAP, and trace levels of
25 organic HAP.
    The emissions data, calculations and risk assessment inputs for the
Primary Lead Smelting source category are described further in the
Technical Support Document for this action which is available in the
docket for this proposed rulemaking.
    We used the 2008 production information as the basis for
calculating the MACT allowable ratio (allowable to actual) because the
2008 emissions are the most recent reported emissions that also reflect
implementation of the requirements of the 2007 SIP revision. For more
information on the ratio of actual to MACT-allowable emissions, see the
Technical Support Document in the docket for this action describing the
emission data information and estimation of MACT-allowable emission
levels and associated risks and impacts.

B. What are the results of the risk assessments and analyses?

    For the Primary Lead Smelting source category, we conducted an
inhalation risk assessment for all HAP emitted. We also conducted a
multi-pathway analysis for cadmium and lead. With respect to lead, we
used the recently-promulgated lead NAAQS to evaluate the potential for
multi-pathway and environmental effects. Furthermore, we conducted a
demographic analysis of population risks. Details of the risk
assessments and additional analyses can be found in the residual risk
documentation referenced in section IV.A of this preamble, which is
available in the docket for this action.
1. Inhalation Risk Assessment Results
    Table 3 provides an overall summary of the results of the
inhalation risk assessment.

                                            Table 3--Primary Lead Smelting Inhalation Risk Assessment Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
   Maximum individual cancer risk  (in 1                                                   Maximum chronic non-cancer  TOSHI \2\
               million) \1\                       Estimated         Estimated annual   --------------------------------------------   Maximum off-site
-------------------------------------------  population at risk     cancer incidence                                                 refined acute  non-
  Actual  emissions   Allowable  emissions    >= 1-in-1 million     (cases per year)      Actual  emissions   Allowable  emissions      cancer HQ \3\
        level                 level                                                             level                 level
--------------------------------------------------------------------------------------------------------------------------------------------------------
               30                    30                 4,900                0.0008                     1                     1                   0.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Estimated maximum individual excess lifetime cancer risk.
\2\ Maximum TOSHI. The target organ with the highest TOSHI for the Primary Lead Smelting source category is the kidney.
\3\ The maximum acute HQ value shown uses the only available acute dose-response value for arsenic, which is the REL. See section IV.A of this preamble
  for explanation of acute dose-response values.

    The results of the chronic inhalation cancer risk assessment
indicate that, based on estimates of actual emissions from the base
year 2008, the maximum individual lifetime cancer risk could be as high
as 30-in-1 million with fugitive dust emissions of cadmium dominating
the risk. The total estimated cancer incidence from this source
category based on actual emission levels is 0.0008 excess cancer cases
per year or one case in every 1,250 years. Approximately 200 people
were estimated to have cancer risks above 10-in-1 million and
approximately 4,900 people were estimated to have cancer risks above 1-
in-1 million. When considering the maximum levels of emissions allowed
under the current MACT standard, the MIR remains 30-in-1 million. The
MIR remains the same since the fugitive dust emissions are governed by
work practices, which under Sec.  63.1544 are defined as the measures
that will be ``put into place to control fugitive dust emissions.''
Thus, the actual emissions, which reflect the measures that have been
put in place, should be equivalent to the allowable emissions.
    The maximum chronic noncancer TOSHI value is 1, with fugitive
emissions of cadmium dominating those impacts. When considering MACT
allowable emissions, the maximum chronic noncancer TOSHI value remains
1 since, for the reasons provided above, MACT-allowable fugitive
emissions are equal to actual fugitive emissions.
    Based on the acute REL value for arsenic, an off-site screening-
level acute HQ value from this facility could be as high as 6. However,
the emissions factor of 10 times the average hourly emissions rate is
not appropriate in this instance, given that fugitive emissions are
minimized during the meteorological conditions associated with the
worst-case short-term impacts (i.e., during low-wind, stable
atmospheric conditions). Thus, we refined the assessment and estimated
a maximum off-site HQ value of 0.6.
    The results of a multipathway screening analysis for cadmium
emissions from this facility were well below the de minimis emission
rate that would indicate a non-negligible risk of adverse health
effects from multipathway exposures. We estimate the specific
multipathway de minimis emission rate for cadmium to be 0.65 TPY and
only 0.1 TPY is emitted from the one facility in this source category.
Thus, there appears to be little, if any, multipathway risk associated
with cadmium emissions from this facility.
    In evaluating the potential multi-pathway risks from emissions of
lead compounds, we compared modeled maximum 3-month rolling average
atmospheric concentrations with the NAAQS for lead. Table 4 presents
the results of our lead impact analysis broken down by emission point
considering actual 2008 emissions as well as the maximum emissions of
lead that the MACT standard would have allowed based on production
rates for calendar year 2008. For purposes of our analysis, we
determined separately the risk from each of the types or processes/
emissions sources regulated by the current MACT, with one exception.
Under the MACT, emissions from the refining and casting area were
considered fugitive emissions subject to work practice standards under
Sec.  63.1544. Since then, pursuant to requirements that the 2002 State
SIP adopted for purposes of meeting the 1.50 [mu]g/m\3\ lead NAAQS, Doe
Run enclosed the refining and casting area and vents those emissions to
the refinery stacks. We considered these stack emissions separate from
the fugitive dust emissions. Thus, the four emission process/sources we
evaluated for risk were: (1) The main stack, (2) the furnace area
stack, (3) the refinery stack, and (4) fugitive emissions.
    The analysis indicates that under both actual 2008 or MACT
allowable emission scenarios, emissions from the main stack do not
result in lead levels above the NAAQS within the 50 km radius that was
modeled. This is likely due to the height of the stack (500 feet),
which would result in broader and further dispersal of lead emissions.
However, results of the analysis did indicate that modeled ambient air
lead concentrations resulting from this facility's fugitive dust
emissions could exceed the NAAQS for lead by as much as 50-fold at the
property boundary based on both actual and allowable emissions.
Moreover, results indicate that modeled emissions from the furnace area
stack could result in NAAQS exceedances under both actual 2008 and
MACT-allowable emissions scenarios. In addition, the actual estimated
emissions from the refining stacks, which were put into place based on
requirements adopted by the State for purposes of the SIP, could result
in NAAQS exceedances. We were unable to calculate a ``MACT allowable''
emission level for the refinery emissions, which under the MACT are
included as fugitive emissions. This analysis also indicates that
within 50 km of this facility, approximately 1,900 people could be
exposed to ambient air lead concentrations exceeding the level of the
NAAQS for lead.
    As mentioned above, to evaluate the potential for adverse
environmental effects, we also compared maximum 3-month rolling average
atmospheric concentrations with the current secondary NAAQS for lead,
which is the same as the primary standard. Thus, the analyses presented
in Table 4 also indicate the potential for adverse environmental
effects from emissions of lead. Note that modeling performed for this
analysis is based on different inputs than SIP modeling done for the
one remaining primary lead facility, and thus results differ.

  Table 4--Summary of Modeled Lead Concentrations Relative to the NAAQS Based on Estimated Actual 2008 and MACT
                                               Allowable Emissions
----------------------------------------------------------------------------------------------------------------
                                    Actual
                                     2008       Maximum impact--    Allowable      Maximum impact-- allowable
         Emission point            emissions    actual emissions    emissions              emissions
                                     (TPY)                          \1\ (TPY)
----------------------------------------------------------------------------------------------------------------
Main stack \2\..................       13.31  0.05 times the             65.8  0.25 times the NAAQS.
                                               NAAQS.
Refining stacks.................        2.74  3 times the NAAQS..          NA  NA.
Furnace area stack: (controlled         1.81  2 times the NAAQS..        8.94  10 times the NAAQS.
 blast and drossing fugitives).
Fugitive dust \3\...............        2.85  50 times the NAAQS.        2.85  50 times the NAAQS.
----------------------------------------------------------------------------------------------------------------
\1\ Allowable emissions for the main stack and furnace area emission points are based on 1 lb of Pb/ton
  production (MACT limit); Refinery emissions are included as fugitive emissions under MACT but are now vented
  to a stack because of SIP requirements; therefore, we were unable to calculate a ``MACT allowable'' emission
  level.
\2\ Main stack is the emission point for sinter machine, blast furnace and drossing operations.

\3\ Fugitive dust emissions are covered by work practices under current MACT and were calculated via emission
  factors assuming compliance with the MACT. The site of maximum ambient air lead concentration resulting from
  fugitive dust emissions occurs in close proximity to the southeast boundary of the facility (see Figure 3.1-1
  of the risk assessment document). Note that this maximum result and its location are based on modeling 2008
  emissions using 1998 site-specific meteorology, and that these may differ from inputs used for other types of
  modeling (e.g., SIP modeling.)

2. Facility-wide Risk Assessment Results
    Our screening analysis determined that the organic HAP emissions
from facility represented negligible risk and were determined to be
insignificant with regard to this risk analysis. As a result, all
significant HAP emissions from the one facility in this category are
reflected in the risk analyses presented above; therefore, facility-
wide risks are equivalent to those of the source category.
3. Model to Monitor Comparison
    In addition to the results presented above, we also compared
maximum AERMOD estimates of ambient air lead concentrations with those
measured at 4 monitors in close proximity to the Herculaneum Primary
Lead Smelting Facility for calendar year 2008. More specifically, we
compared maximum 3-month rolling average lead concentrations (for
calendar year 2008) calculated from data reported at the Main Street,
Circle Street, South Cross, and Church Street monitors to the maximum
3-month rolling average lead concentrations at model receptor locations
in close proximity to these monitoring sites. These monitor locations
were chosen because they represented the closest offsite monitors to
the Herculaneum primary lead smelter. Thus, lead measurements at these
monitoring sites would likely be dominated by emissions from this
facility which is important given that AERMOD estimates of ambient air
lead concentrations only considered lead emissions from this facility
(i.e., only lead emissions from the Herculaneum primary lead smelter
were used as inputs into AERMOD).
    Results of this analysis are presented in Table 5 and indicate that
with respect to the Main Street and Circle Street monitors, AERMOD
underestimates 3-month maximum lead concentrations by approximately
2.8- and 4.2-fold, respectively. While these monitor to model
comparisons are not in complete agreement on a point-by-point basis, we
note that this would not be expected given the general uncertainties
associated with using dispersion modeling to estimate ambient pollutant
concentrations and considering that the meteorological data used to
develop the model estimates were from a different year than the actual
monitoring and emissions data (i.e., meteorological data used in the
AERMOD simulation was from 1998 while the emissions estimates and the
monitoring data were from 2008). However, results do indicate that the
maximum 3-month average lead concentration across the group of monitors
nearest the facility is approximately equal to the maximum 3-month
average lead concentration estimated by AERMOD across the group of
these monitoring sites (i.e., both the Main Street monitor and the
South Cross AERMOD estimate indicate the maximum 3-month average lead
concentration to be approximately 2.1 [micro]g/m3). Taken together,
these results indicate that AERMOD estimates of ambient air lead
concentration provide a reasonable representation of the measured 3-
month maximum lead concentrations present in the ambient air near this
facility.
---------------------------------------------------------------------------

    \20\ Maximum 3-month monitored concentrations were calculated
for the year 2008 based on data submitted to EPA's Air Quality
System (AQS).
    \21\ Negative sign denotes an underestimation of AERMOD modeled
ambient lead concentrations, relative to monitored concentrations.
AERMOD estimated concentrations were based on the 2008 emissions
estimates described in section V.A.

 Table 5--Comparison of AERMOD Modeled to Ambient Air Lead Concentrations Reported by Four Monitors Surrounding
                                 the Herculaneum Primary Lead Smelting Facility
----------------------------------------------------------------------------------------------------------------
                                                          Maximum AEMOD     Maximum monitored 3-
                                                         modeled 3-month         month lead          Model to
                       Location                         lead concentration   concentration \20\   monitor ratio
                                                           ([mu]g/m\3\)         ([mu]g/m\3\)           \21\
----------------------------------------------------------------------------------------------------------------
Main Street..........................................                 0.47                 3.14             -4.6
Circle Street........................................                 0.38                 1.14             -3.0
South Cross..........................................                 2.13                 0.75              2.8
Church Street........................................                 1.99                 0.47              4.2
----------------------------------------------------------------------------------------------------------------

4. Demographic Risk Analysis Results
    Demographic analyses were performed to investigate the population
distribution of: (1) Cancer risks at or above 1-in-1 million and (2)
risks from ambient air lead concentrations above the NAAQS for lead.
Results are summarized in Table 5 and are based on modeling using
estimated actual emissions levels for the population living within 50
km of this facility.

                        Table 6--Primary Lead Smelting Demographic Risk Analysis Results
----------------------------------------------------------------------------------------------------------------
                                                                                Population with
                                                                             Population with    ambient air lead
                                                             Nationwide        cancer risk       concentrations
                                                                            greater than 1 in    exceeding the
                                                                                a million            NAAQS
----------------------------------------------------------------------------------------------------------------
Total population.......................................      285,000,000              4,900              1,900
----------------------------------------------------------------------------------------------------------------
                                                 Race by percent
----------------------------------------------------------------------------------------------------------------
White..................................................               75                 96                 96

All Other Races........................................               25                  4                  4
----------------------------------------------------------------------------------------------------------------
                                                 Race by percent
----------------------------------------------------------------------------------------------------------------
White..................................................               75                 96                 96
African American.......................................               12                  4                  3
Native American........................................                0.9                0.2                0
Other and Multiracial..................................               12                  1                  0.8
----------------------------------------------------------------------------------------------------------------
                                              Ethnicity by percent
----------------------------------------------------------------------------------------------------------------
Hispanic...............................................               14                  1                  0.3
Non-Hispanic...........................................               86                 99                 99.7
----------------------------------------------------------------------------------------------------------------
                                                Income by percent
----------------------------------------------------------------------------------------------------------------
Below poverty level....................................               13                 15                 15
Above poverty level....................................               87                 85                 85
----------------------------------------------------------------------------------------------------------------

    Results of the risk assessment indicate that there are
approximately 4,900 people exposed to a cancer risk greater than 1-in-1
million, and 1,900 people in areas with ambient air lead concentrations
above the NAAQS for lead. In both instances, the demographics analysis
estimates that about 4 percent of these populations can be classified
as a minority (listed as ``all Other Races'' in the table), which is
well below the national percentage of 25. Similarly, in the cancer and
lead demographic analyses, the percentage of ``African American,''
``Hispanic,'' ``Native American,'' and ``Other and Multiracial''
population groups are well below the corresponding national
percentages. With respect to the percentage of those ``Below the
Poverty Level,'' in both demographic analyses there is a small (2
percent) increment above the corresponding national percentage.
However, given that the total population affected is small (i.e., 4,900
individuals for cancer risk greater than 1-in-1 million and 1,900
individuals in areas with lead concentrations above the NAAQS), we do
not think this indicates any significant potential for disparate
impacts to the specific demographic groups analyzed.
    Moreover, given the extent to which lead may impact children's
health, we further note that our demographic analysis doesn't indicate
the presence of a higher percentage of children than one would normally
expect around this facility. That is, while the national percentage of
children 18 years and younger is 27%, the percentage of children living
near this facility who are estimated to be exposed to lead
concentrations above the NAAQS is only slightly higher at 28% (see Risk
and Technology Review--Analysis of Socio-Economic Factors for
Populations Living Near Primary Lead Smelting Facilities in the docket
for this proposed rulemaking), a difference which is likely not
significant.

C. What are our proposed decisions on risk acceptability and ample
margin of safety?

1. Risk Acceptability
    As noted in section III.B of this preamble, we weigh all health
risk factors in our risk acceptability determination, including cancer
risks to the individual most exposed, risk estimation uncertainty, and
other health information. For the Primary Lead Smelting source
category, the risk analysis indicates that the cancer risks to the
individual most exposed could be as high as 30-in-1 million due to
actual or MACT-allowable emissions. These risks are considerably less
than 100-in-1 million, which is the upper bound of the presumptive
range of acceptability. The incidence of cancer is very low--0.0008
excess cancer cases per year; or one case every 1,250 years. Similarly,
the risks of chronic non-cancer health effects from HAP emissions other
than lead were low, with a maximum HQ of 1. Moreover, while an initial
screening analysis suggested that fugitive emissions of arsenic had the
potential to create a risk of acute health effects, a refined analysis
based on our knowledge of this emission source indicated that the risk
was low (HQ = 0.6). In addition to these health analyses, a
demographics analysis did not indicate the potential for significantly
disproportionate heath impacts (see above, section V(3)(c)). Thus,
risks associated with the non-lead emissions from the Primary Lead
Smelting source category for cancer, acute and chronic non-cancer
health effects and environmental effects are considered acceptable.
    However, since ambient air lead concentrations resulting from
emissions from this facility were modeled to be in excess of the NAAQS
for lead, the risks associated with lead emissions from this facility
were judged to be significant. Our analysis estimated that modeled off-
site ambient air lead concentrations (based on actual 2008 emissions)
resulting from this facility could be as high as 50 times the NAAQS for
lead based on fugitive dust emissions, and that approximately 1,900
individuals could be exposed to lead concentrations in excess of the
NAAQS. Given that the NAAQS for lead was set to ``provide increased
protection for children and other at-risk populations against an array
of adverse health effects, most notably including neurological effects
in children, including neurocognitive and neurobehavioral effects (73
FR 67007)'', we are proposing that risks associated with lead emissions
from this source category are unacceptable.
    As noted above, our risk analysis for lead was based on modeled 3-
month rolling average lead concentrations in ambient air in comparison
to the primary lead NAAQS. We believe that in order to provide an
acceptable level of risk, lead concentrations in the ambient air must
be reduced to the level of the lead NAAQS. Thus, we

considered specific emission limits for the three emission sources/
points that were modeled to result in lead concentrations in excess of
the NAAQS (see Table 4); refinery stack, furnace area stack, and
fugitive dust emissions, with the majority of fugitive dust impacts
from material handling sources. Based on our analysis, we conclude that
in order to meet the NAAQS for lead at all model receptors, fugitive
dust emissions would have to be reduced by approximately 98 percent to
0.064 TPY, refinery stack emissions and furnace area stack emissions
would have to be reduced by approximately 80 percent to a total of 0.91
TPY (the maximum impacts of refinery and furnace emission points occur
at the same location.) Further, because the maximum ambient air impacts
of the refinery/furnace emissions, the fugitive dust emissions, and the
main stack do not significantly overlap each other, we estimate that
lead emissions from all emission points other than the main stack would
have to be limited to a total of approximately 0.97 TPY in order to
ensure 3-month rolling average ambient air lead concentrations do not
exceed the lead NAAQS level of 0.15 [mu]g/m\3\. As noted above,
emissions from the main stack (i.e., emission point for sinter machine,
blast furnace and drossing operations) did not result in ambient air
lead concentrations in excess of the lead NAAQS at modeled locations
within 50 km of the property boundary and thus we are not proposing any
reductions at the main stack in order to ensure an acceptable level or
risk.
    Once we determined the emissions reductions necessary to achieve an
acceptable level of risk, we investigated available emissions control
options and their ability to reduce emissions and health risks for
fugitive dust and for stack emissions from both the refining and
furnace area stacks. Control options considered for reducing fugitive
dust emissions and associated risks include improved or additional work
practices, site remediation, application of additional capture/control
measures, and lead production limitations. With the exception of site
remediation, all of these control measures have been implemented to
varying degrees at the Doe Run facility in response to the Missouri
SIP, as revised in 2002 and the 2007 revisions submitted for approval
to the SIP. As such, because the actual emissions for 2008 reflect the
implementation of those control measures, requiring those controls
under the MACT would be unlikely to yield the additional 98 percent
reduction in fugitive emissions necessary to meet the primary lead
NAAQS level of 0.15 [micro]g/m \3\. Thus, our evaluation of risks based
on actual emissions already considered emissions with these controls
largely in place. In order to ensure that site remediation efforts, or
any other efforts the source may choose to undertake, will result in
sufficient emission reductions to address the unacceptable level of
risk, we are proposing to establish a lead concentration in air limit
of 0.15 [micro]g/m \3\ to be measured at locations approved by the
Administrator. This lead concentration in air limit would be
established as the enforceable requirement to address fugitive
emissions under the MACT standard.\22\ Because we are proposing a
concentration limit to address fugitive dust emissions, we no longer
believe it is necessary for the affected facility to provide a plan to
the Administrator describing work practices that will be used to reduce
fugitive emissions. Therefore, we are proposing to remove the
requirement to develop and submit a work practice standard operating
procedure (SOP) manual as required in Sec.  63.1544(a).
---------------------------------------------------------------------------

    \22\ Under the consent decree, of which we sought public comment
last fall, fugitive dust sources will be addressed by site
remediation; however, some fugitive dust emissions will remain
during the remediation of the site, which will likely extend beyond
April 2014.
---------------------------------------------------------------------------

    As an alternative to proposing compliance monitoring requirements
for demonstration of compliance with the lead concentration in air
limit, we considered retaining the current fugitive dust emissions
requirement to develop and submit to the Administrator or delegated
authority a work practices SOP. Using this alternative approach, we
believe it would be necessary to modify the current general
requirements for an SOP by specifying the minimum work practice
requirements that the plan must include. For example, under this
alternative approach, we would require that the SOP must include, at a
minimum, detailed descriptions of all measures that would be used to
control fugitive dust emissions from plant roadways; material storage,
transfer and handling areas; sinter machine areas; furnace areas;
refining and casting areas; and other areas the Administrator may
identify. Further, EPA would require that the SOP contain detailed
descriptions of work practices including road watering and automatic
sprinklers, methods to remove dust from paved surfaces to reduce
emissions from traffic, maintenance of minimum water content for ore
concentrate and for baghouse dust that will be handled or transferred,
and procedures for the inspection of building siding or damages and
openings. The SOP would be required to include procedures, including
recordkeeping, to ensure that the work practices are being implemented
at a frequency and in a manner that would ensure that fugitive dust
emissions are being minimized. To determine whether the work practices
described in the SOP are reducing emissions sufficient to comply with
the lead concentration in air limit, the owner or operator would be
required once a year to model the fugitive dust emissions using
measurement data or emission factors according to an approved fugitive
dust emissions modeling plan. At a minimum, EPA would require that this
modeling plan include a detailed description of each fugitive dust
emission source; a detailed description of the control practices or
techniques used to limit fugitive dust emissions from each source; the
emission factors, test data or other methods used to characterize and
quantify lead emissions from each source; a description of the
emissions modeling that will be used to estimate the concentrations of
lead in air at or near the property boundary as contributed by each
source as well as cumulatively contributed by all sources; a
description of process or other conditions that would indicate the need
to demonstrate compliance more often than annually; the calculations to
be used to show compliance with the air lead concentration limit that
consider the highest modeled air lead concentrations from the modeled
fugitive dust sources and any contributions from background lead
concentrations in air; and a description of the records that will be
kept. We are seeking comments on the proposed requirements to monitor
air lead concentrations versus the alternative approach described
above, of requiring extensive work practices and a work practice SOP in
conjunction with emissions modeling, to demonstrate compliance with the
air lead concentration limit.
    Measures available for reducing lead emissions from the refining
and furnace area stacks include upgrading existing baghouses by
replacing the existing fabric bags with high efficiency membrane bag
filters. Another option would be to add extra in-line baghouses after
existing baghouses. Such measures would reduce lead emissions and
associated risk to within acceptable levels.
    In summary, our analysis indicates that in order to ensure that
lead emissions from this source do not pose an unacceptable risk,
emissions from

this facility would need to be reduced to a level that would ensure
that these emissions would not result in air lead levels greater than
the 0.15 [micro]g/m \3\ for any 3-month period at all of the modeled
locations. Further, we conclude that in order to achieve the 0.15
[micro]g/m \3\ level (for any 3-month rolling average) at all modeled
locations, fugitive dust emissions would need to be reduced by 98
percent and the emissions from the furnace area and refining operation
stacks would need to be reduced by 80 percent. We have identified
emission reduction and control options for achieving the required
reductions, which include implementation of site remediation, work
practices, and upgrade of existing baghouses with membrane bags and/or
addition of an additional in-series baghouse.
    We are proposing the following requirements to ensure that risk is
reduced to an acceptable level.
     A stack lead emission cap of 0.91 TPY that would apply to
the furnace area stack and the refining operation stacks.
     An air lead concentration limit of 0.15 [micro]g/m\3\
based on 3-month rolling average (to be measured at locations approved
by the Administrator) to ensure that fugitive dust emission levels will
not exceed the NAAQS.
    The proposed limits apply to both new and existing facilities. Any
facility subject to the MACT would be required to meet these
requirements for each emission unit it is operating that is subject to
the limit. In order to address any fugitive dust emissions, the
facility, regardless of whether it is operating all or just some of the
emission sources covered by this action, would be required to meet the
air lead concentration emission limit.
    For both new and existing facilities, compliance with the air lead
concentration limit would be demonstrated using lead compliance
monitoring devices and would be based on a rolling 3-month average
concentration. The proposed rule requires development of a monitoring
plan for approval by the Administrator that includes the minimum
sampling and analysis methods and compliance demonstration criteria
provided in the rule. A provision is included in this proposed rule
that allows for reduced monitoring if the facility demonstrates an air
lead concentration for three consecutive years at less than 50 percent
of the air lead concentration limit. The monitoring can be reduced to
once every six months unless one of the 6-month monitoring events
exceeds 50 percent of the air lead concentration limit, at which time
monitoring will be required to resume based on the initial plan
approved by the Administrator until another three years of consecutive
monitoring below 50 percent of the air lead concentration limit is
achieved. The compliance requirements discussed above were designed to
allow for flexibility, prevention of redundant requirements, and also
to provide consistency with current monitoring required at the site. We
are soliciting comment on this approach. For existing facilities,
compliance with the emission limit for the furnace area and refinery
stacks would be demonstrated through stack testing conducted on a
quarterly basis. All performance testing will be consistent with the
existing MACT testing requirements, with the exception of frequency. As
provided in Sec.  63.153(e) of the current rule, the facility can
reduce compliance testing frequency if the most recent three compliance
tests demonstrated compliance. We are maintaining this provision,
however, because this proposed rule increases the testing frequency to
quarterly, the number of most recent tests necessary to comply with
this provision will be increased from three to 12. New primary lead
processing facilities would be required to demonstrate compliance using
a lead continuous emission monitoring systems (CEMS). However, since
the Agency has not finalized the performance specification for the use
of these instruments, we are deferring the effective date of the
requirement to install, correlate, maintain and operate lead CEMS until
these actions can be completed. The lead CEMS installation deadline
will be established through future rulemaking, along with other
pertinent requirements. In the event operations commence at a new
facility prior to promulgation of the performance specification,
compliance would be demonstrated through quarterly stack testing until
promulgation of the lead CEMS performance specification.
2. Ample Margin of Safety
    Reducing lead emissions to meet the NAAQS would ensure that
emissions of all HAP do not pose an unacceptable risk. Once we ensure
that the risk is acceptable, we then look to determine whether further
reductions are appropriate to ensure an ample margin of safety. In this
part of our analysis, we again consider the health factors we
considered to determine whether the risks are acceptable but we also
consider the cost of controls.
    With regard to lead emissions, we are proposing to require most of
the emission sources at the facility to implement all technically
feasible controls in order to ensure that the ambient air meets the
level of the lead NAAQS, which is the level that we have determined
will ensure an acceptable level of risk. Because all feasible controls
will need to be adopted in order to meet that proposed standard, there
are no additional controls to consider for the three emission sources:
Fugitive dust emissions, the furnace area stack, and the refinery
stacks. We further note that the same controls we have proposed for the
three emission points to reduce lead emissions are the same controls
that would reduce risks from cadmium and all other metal HAP known to
be emitted from this source category. Thus, we are proposing that the
controls required to ensure that risk from lead emissions from those
three emission points is acceptable also protect public health with an
ample margin of safety with regard to emissions from all metal HAP from
these three emission points. Notably, after these standards are in
place, we estimate that the MIR cancer risk due to the non-lead HAP
will be less than 1-in-1 million.
    Our risk analysis indicates that the main stack emissions do not
result in ambient air lead levels exceeding the NAAQS based on either
actual or allowable emission levels. We determined, as discussed
section V.D. below, that it is technologically feasible to reduce
emissions from the main stack to a level well below the allowable level
of the MACT, since those levels are currently being achieved, and thus
we are proposing to require such controls under CAA section 112(d)(6).
We evaluated whether there were additional controls to further reduce
emissions from the main stack and determined that lead emissions from
the main stack could be further reduced by replacing the standard cloth
bags with membrane bags at a capital cost of approximately $2 million
and an annual cost of $0.3 million. Assuming a 50 percent reduction
from 2008 main stack emissions, the cost of reducing lead emissions
would be about $40,000 to $229,000 per ton of lead. (See the Technical
Support Document included in the docket for a complete discussion of
this analysis.) Because the highest ambient air lead concentration
resulting from the emissions from the main stack already is more than
20 times below the level that is considered acceptable, it was
determined that although additional controls such as membrane bags
could result in additional emission reductions, the additional controls
are not warranted since they would not

appreciably reduce risk. We are proposing that the MACT standard, with
the changes we are proposing under the section 112(d)(6) technology
review as described in section V.D. below will provide an ample margin
of safety with regard to emissions of lead and other HAP from the main
stack.

D. What are the results and proposed decisions from the technology
review?

    We evaluated developments in practices, processes, and control
technologies applicable to emission sources subject to the Primary Lead
Smelting MACT. This included a search of the RBLC Clearinghouse, the
California BACT Clearinghouse, the internet, and correspondence with
state agencies and industry. We have determined that there have been
advances in emission control measures since the Primary Lead Smelting
MACT standard was originally promulgated in 1999.
    The 1999 MACT limit was set using the lead emission limits from the
lead SIPs for the three states in which primary lead smelting sources
were operational at the time of the rulemaking. EPA took each of the
three lead SIP limits, in lb/day, divided them by the corresponding
lead production capacity, in tons/day, and calculated a lead emission
rate in lb/ton. The results were as follows:

ASARCO--Missouri 1.0 lb/ton
ASARCO--Montana 1.0 lb/ton
Doe Run--Missouri 0.84 lb/ton

    The values were ranked and the median value (1.0 lb/ton) was
selected as representative of the MACT floor.
    Since the MACT standard was promulgated, the industry has undergone
significant changes. Two of the three facilities have shut down. The
only remaining primary lead smelting facility is the Doe Run smelter at
Herculaneum, Missouri, which is subject to control requirements under
the Missouri SIP for lead. The existing SIP, as well as a 2007 SIP
revision submitted by the State and proposed for approval by EPA
require numerous emissions-reducing measures and improvements to add-on
control devices, processes, and work practices. We considered these
developments in practices, processes, and control technologies in our
technology review.
    Recent emissions tests (2000 through 2008) at the Doe Run facility
support that these improvements have resulted in significantly lower
emissions and demonstrate that actual lead emissions from the facility
are much lower than are allowed under the current MACT rule. To assess
the impacts of developments in practices, processes and control
technologies on lead emissions, emissions data from 2008 were compared
with emissions data from 2000. Data from 2008 were selected because
they reflect the many improvements that have been implemented at the
facility since promulgation of the MACT rule. Emissions data from
earlier years would not reflect all of the emission-reducing changes
that have been implemented at the Doe Run facility given that some of
the improvements were not implemented until 2007 and 2008. As described
above, technological improvements to baghouses and processes that have
been implemented at the facility since the MACT rule was promulgated
have resulted in substantially lower emissions from these sources at
this facility. These improvements include upgrade of cloth bags and
ventilation improvements. In 2008, lead emissions from the main stack,
which vents emissions from the sintering operation and the blast and
dross furnace, were 13.31 TPY. In addition, emissions from the furnace
area stack (i.e., the blast furnace and dross plant building which vent
to baghouse 7) were 1.81 TPY, for a total of approximately 15.1 TPY. At
the 2008 lead production rate of 149,500 tons, the lead emission rate
for these sources at Doe Run was about 0.2 lb/ton, or 80 percent less
than the current MACT limit of 1 lb/ton. Based on this demonstrated
performance, EPA believes that under Section 112(d)(6), the MACT
standard should be revised to reflect the reduction achieved in
practice.
    Because we believe that the 2008 emissions of 13.31 TPY from the
main stack (or combined sintering/blast furnace/drossing operations)
reflect the annual rate of emissions achievable as a result of the
technological improvements that have been made since 1999, we are
proposing an emission limit based on the actual 2008 annual emissions
that vent to the main stack (i.e., sintering, blast furnace and
drossing operations). In order to account for variability in the
operation and emissions, recent stack tests were used to calculate the
95 percent upper predictive limit (UPL). The 95 percent UPL for the
main stack is 15 TPY. Variability in the operations and emission for
this source are discussed in more detail in Section E below.
    Although we believe that there have been developments in processes,
practices and control technologies with regard to the furnace area
stack and with regard to refining and casting operations, as reflected
by the more stringent requirements that have been implemented in
accordance with the approved SIP and the 2007 SIP revisions; we are not
proposing additional requirements for these stacks as part of our
technology review because we have already proposed that these stacks
implement all feasible controls, regardless of cost, in order to ensure
that the risks due to these emission points are acceptable. Thus, there
are no additional developments in practices, processes and control
technologies beyond those which are reflected in the emission limits we
have proposed to meet CAA section 112(f)(2), above.
    To be consistent with the existing MACT standard, EPA is proposing
to retain the plant-wide pound per ton of production format that
currently applies to the aggregate emissions from the main stack and
the furnace area stack. Because there are also stacks for the refining
and casting operations, we are proposing to include those emissions as
part of the plant-wide emission limit. Thus we are proposing a plant-
wide lead emission limit of 0.22 pounds of lead per ton of lead
produced based on the proposed reductions due to the section 112 (f)(2)
risk review for the furnace area and refining operations stacks
(discussed above in Section C) and the reduction in emissions from the
main stack (sinter/blast furnace/drossing operations) based on this
Section 112(d)(6) technology review This proposed plant-wide lead
emission limit was determined by summing the 15 TPY for the main stack
and the 0.91 TPY for the furnace area and the refining operation, and
dividing by the annual production from 2008 of 149,564 tons. We note
that variability was only applied in establishing technology-based
emissions from the main stack in order to establish a plant-wide
emission limit. Because the emission levels required from the refining
operation and furnace area stacks are based on acceptable risk, we
conclude it is not appropriate to consider variability in establishing
limits for these emission points.
    We are proposing that the plant-wide lead emission limit apply to
new and existing facilities that are subject to the MACT. By default
this would include any new, controlled lead processing source not
currently covered, including lead processing by other than the current
techniques. We are requesting comment on the appropriateness of
applying the plant-wide lead emission limit to any future new lead
processing technique.
    For the existing facility, compliance with the plant-wide stack
emission limit would be demonstrated in the same

manner as discussed above in section V.C.1 for the furnace area and
refining stack limit (i.e., stack testing on a quarterly basis). We are
proposing stack testing on a quarterly basis as opposed to testing on
an annual basis since this allows the facility the opportunity to
adjust their emissions throughout the year to be in compliance, rather
than to find they are out of compliance at the end of the year, thereby
risking violations. This schedule also coincides with other quarterly
monitoring and reporting required of the facility. Also as discussed in
section V.C.1, new primary lead processing facilities would be required
to demonstrate compliance using lead continuous emission monitoring
systems (CEMS).

E. Variability

    In assessing sources' performance, EPA may consider variability
both in identifying which performers are ``best'' and in assessing
their level of performance. Brick MACT, 479 F. 3d at 881-82; see also
Mossville Envt'l Action Now v. EPA, 370 F.3d 1232, 1241-42 (D.C. Cir
2004) (EPA must exercise its judgment, based on an evaluation of the
relevant factors and available data, to determine the level of
emissions control that has been achieved by the best performing sources
considering these sources' operating variability).
    Variability in lead producers' performance has a number of causes.
For emissions of lead compounds that are controlled by baghouses, the
variability is chiefly due to variations in performance of the control
device for which both run-to-run and test-to-test variability must be
accounted.\23\
---------------------------------------------------------------------------

    \23\ Run-to-run variability is essentially within-test
variability, and encompasses variability in individual runs
comprising the compliance test, and includes uncertainties in
correlation of monitoring parameters and emissions, and imprecision
of stack test methods and laboratory analysis. 72 FR 54877 (Sept.
27, 2007). Test-to-test variability results from variability in
pollution device control efficiencies over time (depending on many
factors, including for fabric filters the point in the maintenance
cycle in which a fabric filter is tested). Test-to-test variability
can be termed long-term variability. 72 FR 54878.
---------------------------------------------------------------------------

    In determining the contribution to a plant-wide emission limit of
the main stack, we considered annual emissions discharged from the air
pollution control devices that control lead emissions. For this rule,
we used the 2008 emissions reported by Doe Run to the State of
Missouri.
    We assessed variability using a statistical formula designed to
estimate an emissions level that is equivalent to the source's
performance based on future compliance tests. Specifically, the
calculated limit is an upper prediction limit (UPL) calculated with the
Student's t-test using the TINV function in Microsoft Excel[supreg].
The Student's t-test has also been used in other EPA rulemakings (e.g.,
NESHAP for Portland Cement Manufacturing [75 FR 54970, September 9,
2010]; NSPS for Hospital/Medical/Infectious Waste Incinerators [74 FR
51368, October 6, 2009]; NESHAP for Industrial, Commercial, and
Institutional Boilers and Process Heaters-Proposed [75 FR 32006, June
4, 2010]) in accounting for variability. A prediction interval for a
future observation is an interval that will, with a specified degree of
confidence, contain the next (or some other pre-specified) randomly
selected observation from a population. In other words, the prediction
interval estimates what the upper bound of future values will be, based
upon present or past samples taken. The UPL consequently represents the
value which we can expect the mean of future observations (3-run
average for lead) to fall below within a specified level of confidence,
based upon the results of an independent sample from the same
population. In other words, if we were to randomly select a future test
condition from any of these sources (i.e., average of 3 runs or 30-day
average) we can be 95 percent confident that the reported level will
fall at or below the UPL value. Use of the UPL is appropriate in this
rulemaking because it sets a limit any single or future source can meet
based on the sources past performance.
    This formula uses a pooled variance (in the s\2\ term) that
encompasses all the data-point to data-point variability. Where
variability was calculated using the UPL statistical approach, we used
the sample standard deviation calculated from the emissions data
distributions for lead. The standard deviation is the common measure of
the dispersion of the data set around an average. We note here that the
methodology accounts for both short-term and long-term variability and
encompasses run-to-run and test-to-test variability.
    We adopted a form of the UPL equation that has been used in more
recent rulemakings. See 75 FR 54970 (September 9, 2010), 75 FR 32020
(June 4, 2010) and 75 FR 31905 (June 4, 2010). The UPL used in this
proposed rule is calculated by:

[GRAPHIC] [TIFF OMITTED] TP17FE11.000

Where:

x = 2008 annual emissions
n = the number of test runs
m = the number of test runs in the compliance average
s\2\ = observed variance
t = student t distribution statistic

This calculation was performed using the following Excel functions: 95
percent UPL = 2008 annual emissions + [STDEV (Test Runs) x TINV (2 x
probability, n-1 degrees of freedom) x SQRT ((1/n) + (1/m))], for a
one-tailed t-value, probability of 0.05, and sample size of n.

F. What other actions are we proposing?

    As discussed in Section III.C. above, EPA is proposing to remove
provisions in the existing standard that would have exempted sources
from complying with the standard during periods of startup, shutdown
and malfunction. Specifically we are proposing revisions to subpart TTT
Table 1 and rule provisions to remove applicability of the General
Provisions with regard to SSM and remove the exemption for bag leak
detection alarm time attributable to SSM events from determining
compliance with the total alarm time limit. In addition, we are
proposing to promulgate an affirmative defense to civil penalties for
exceedances of emission limits caused by malfunctions, as well as
criteria for establishing the affirmative defense.
    EPA has attempted to ensure that we have not included in the
proposed regulatory language any provisions that are inappropriate,
unnecessary, or redundant in the absence of the SSM exemption. We are
specifically seeking comment on whether there are any such provisions
that we have inadvertently incorporated or overlooked.

VI. Proposed Action

A. What actions are we proposing as a result of the residual risk
reviews?

    Consistent with CAA section 112 (f)(2), we are proposing to amend
the MACT standard for primary lead processing to include a lead
concentration in air limit of 0.15 [micro]g/m3 (based on 3-month
rolling averages)to be measured at locations approved by the
Administrator to address the risks from all fugitive dust emissions
addressed in 40 CFR 63.1544. We are also proposing to remove refining
and casting operations from Sec.  63.1544 and to require that emissions
from these operations be vented to one or more stacks. Finally, we are
proposing to establish an emission cap of 0.91 TPY for the furnace area
stack and the refining operation stacks. These limits were established
based on the level of reductions in lead emissions from the three
sources that are necessary to show that the lead NAAQS will not be
exceeded within the 50 km modeled domain. We believe the NAAQS level
represents an acceptable level of risk and that the proposed limits are
necessary to ensure that risks from these sources are acceptable. We
are proposing that the risk posed by lead emissions from the main stack
and by emissions of all other HAP is acceptable.
    We are proposing that compliance with the emission limits
applicable to the furnace area and refinery stacks would be
demonstrated based on stack testing for existing facilities and, for
new facilities, using CEMS after promulgation of performance
specifications for a CEMS capable of measuring lead emissions.
    We are proposing that compliance with the lead concentration in air
limit would be demonstrated using a compliance monitoring system
approved by the Administrator.
    We are also proposing that the Primary Lead Smelting standard, as
we have proposed to revise it to ensure an acceptable level of risk,
will also protect public health with an ample margin of safety. With
regard to lead emissions from fugitive dust sources and from the
furnace and refining area stacks, we have not identified any feasible
controls beyond those needed to meet the proposed emission limits that
will provide an acceptable level of risk . The standards we are
proposing to ensure an acceptable level of risk for lead emissions will
also reduce the risk from cadmium and will also reduce emissions of all
other metal HAP known to be emitted from this source category because
the controls that will reduce lead emissions are the same controls that
will reduce emissions of these other metal HAP. The cancer risk from
cadmium emissions will be reduced from 30-in-1 million to less than 1-
in-1 million. Therefore, we are proposing that the existing MACT, as it
would be modified based on our proposed requirements for lead
emissions, would provide an ample margin of safety with respect to
emissions from all metal HAP.
    With regard to lead emissions from the main stack, we have
identified developments in practices, processes and control
technologies since promulgation of the MACT standard in 1999, and are
proposing a reduced emission limit for the main stack based on these
improvements. Since the main stack does not pose an unacceptable risk
at its current emissions level, we are not proposing reductions for
this emission point under 112(f)(2). However, we are proposing a
reduced emission limit under 112(d)(6) due to the improvements we
identified.

B. What actions are we proposing as a result of the technology reviews?

    For the Primary Lead Smelting source category, we have determined
that there have been developments in practices, processes, or control
technologies since the promulgation of the MACT standards that are
feasible for the one facility in this source category to implement at
the main stack. The proposed limit is consistent with the current
demonstrated performance of the facility based on obligations adopted
by the State and reflected in the 2002 SIP and 2007 SIP revision for
Doe Run.
    We are proposing that a performance of 15.11 TPY has been
demonstrated for emissions from the main stack, taking into
consideration variability of emissions from that stack. The existing
MACT lead emissions standard that is applicable to emissions from the
main stack is a plant-wide emission limit that also applies to
emissions from the furnace-area stack. We are proposing to revise the
plant-wide limit to reflect the 15.11 TPY limit for the main stack as
well as the emissions limits we are proposing for the furnace-area and
refinery stacks under CAA section 112(f)(2). Thus, we are proposing to
revise the plant-wide emissions limit from 1 pound of lead per ton of
lead produced, to 0.22 pound of lead per ton of lead produced and the
new limit would include emissions from the refinery stack as well as
emissions from the main stack and the furnace area stack. Compliance
with this limit would be demonstrated quarterly with stack testing. For
new facilities, compliance would be demonstrated using lead CEMS.

C. What other actions are we proposing?

    As described above, we are proposing to amend the applicability
section for the MACT rule to tailor it to the definition of the source
category we established under CAA section 112(c)(1). See
``Documentation for Development of Initial Source Category List--Final
Report'', USEPA/OAQPS, EPA-450/3-91-030, July, 1992. In support of this
applicability provision clarification, we are also proposing to replace
the definition of ``primary lead smelter'' with a definition of
``primary lead processor''. The ``primary lead processor'' definition
would include any facility that produces lead from processing of lead
sulfide ore by pyrometallurgical (smelting) or any other technique. We
are also proposing to add definitions of ``secondary lead smelters'',
``lead refiners'', and ``lead remelters'' to clarify the meaning of
those terms in the second sentence of the applicability provision.
    We propose to amend the Primary Lead Smelting MACT standards to
remove the language that exempts bag leak detection system alarm time
incurred during periods of SSM from inclusion in the allowable alarm
time. This change is being made to ensure the rule is consistent with
the court's ruling in Sierra Club v. EPA, 551 F.3d 1019 (D.C. Cir.
2008). We are also proposing minor modifications throughout the rule to
incorporate plain language and to make editorial and clarifying
revisions. In addition, we are proposing changes to Table 1 of the rule
to reflect revisions to SSM requirements.

D. Compliance Dates

    We are proposing that the requirements under CAA section 112(f)(2)
for the one existing source, if finalized, must be implemented no later
than two years after the effective date of this rule. Consistent with
CAA section 112(f)(4)(B), we are proposing that a two-year compliance
period is necessary so the facility has adequate time to install
additional controls and demonstrate compliance, including the time
necessary to purchase, install and test replacement bags, or if the
facility decides to add a new baghouse in series with an existing
baghouse, seek bids, select a vendor, install and test the new
equipment; prepare and submit the required monitoring plan to monitor
lead concentrations in air; purchase, install and conduct quality
assurance and quality control measures on compliance monitoring
equipment and; conduct site remediation necessary to

reduce fugitive emissions. A two-year compliance period is also
consistent with the schedule of required actions contained in the
Consent Decree.
    In addition, we are proposing that the plant-wide limit that would
reflect reductions required for the main stack pursuant to CAA section
112(d)(6) and for the furnace area and refinery stacks pursuant to CAA
section 112(f)(2) must be met no later than two years after the
effective date of this rule. Because these limits reflect the
reductions from the furnace area and refinery stacks required under
section 112(f)(2), we believe a two-year compliance timeframe is needed
for the same reasons provided above.

VII. Request for Comments

    We are soliciting comments on all aspects of this proposed action.
All comments received during the comment period will be considered. In
addition to general comments on this proposed actions, we are also
interested in any additional data that may help to reduce the
uncertainties inherent in the risk assessments. We are specifically
interested in receiving corrections to the dataset used for risk
modeling. Such data should include supporting documentation in
sufficient detail to allow characterization of the quality and
representativeness of the data or information. Please see the following
section for more information on submitting data.

VIII. Submitting Data Corrections

    The facility-specific data used in the source category risk
analyses and demographic analyses are available for download on the RTR
Web Page at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. The data files
include detailed information for each HAP emissions release point for
the facility included in the source category.
    If you believe the data are not representative or are inaccurate,
please identify the data in question, provide your reason for concern,
and provide any ``improved'' data that you have, if available. When you
submit data, we request that you provide documentation of the basis for
the revised values to support your suggested changes. To submit
comments on the data downloaded from the RTR Web page, complete the
following steps:
    (1) Within this downloaded file, enter suggested revisions to the
data fields appropriate for that information. The data fields that may
be revised include the following:

------------------------------------------------------------------------
          Data element                          Definition
------------------------------------------------------------------------
Control Measure.................  Are control measures in place? (yes or
                                   no).
Control Measure Comment.........  Select control measure from list
                                   provided, and briefly describe the
                                   control measure.
Delete..........................  Indicate here if the facility or
                                   record should be deleted.
Delete Comment..................  Describes the reason for deletion.
Emission Calculation Method Code  Code description of the method used to
 For Revised Emissions.            derive emissions. For example, CEM,
                                   material balance, stack test, etc.
Emission Process Group..........  Enter the general type of emission
                                   process associated with the specified
                                   emission point.
Fugitive Angle..................  Enter release angle (clockwise from
                                   true North); orientation of the y-
                                   dimension relative to true North,
                                   measured positive for clockwise
                                   starting at 0 degrees (maximum 89
                                   degrees).
Fugitive Length.................  Enter dimension of the source in the
                                   east-west (x-) direction, commonly
                                   referred to as length (ft).
Fugitive Width..................  Enter dimension of the source in the
                                   north-south (y-) direction, commonly
                                   referred to as width (ft).
Malfunction Emissions...........  Enter total annual emissions due to
                                   malfunctions (TPY).
Malfunction Emissions Max Hourly  Enter maximum hourly malfunction
                                   emissions here (lb/hr).
North American Datum............  Enter datum for latitude/longitude
                                   coordinates (NAD27 or NAD83); if left
                                   blank, NAD83 is assumed.
Process Comment.................  Enter general comments about process
                                   sources of emissions.
REVISED Address.................  Enter revised physical street address
                                   for MACT facility here.
REVISED City....................  Enter revised city name here.
REVISED County Name.............  Enter revised county name here.
REVISED Emission Release Point    Enter revised Emission Release Point
 Type.                             Type here.
REVISED End Date................  Enter revised End Date here.
REVISED Exit Gas Flow Rate......  Enter revised Exit Gas Flowrate here
                                   (ft\3\/sec).
REVISED Exit Gas Temperature....  Enter revised Exit Gas Temperature
                                   here (F).
REVISED Exit Gas Velocity.......  Enter revised Exit Gas Velocity here
                                   (ft/sec).
REVISED Facility Category Code..  Enter revised Facility Category Code
                                   here, which indicates whether
                                   facility is a major or area source.
REVISED Facility Name...........  Enter revised Facility Name here.
REVISED Facility Registry         Enter revised Facility Registry
 Identifier.                       Identifier here, which is an ID
                                   assigned by the EPA Facility Registry
                                   System.
REVISED HAP Emissions             Enter revised HAP Emissions
 Performance Level Code.           Performance Level here.
REVISED Latitude................  Enter revised Latitude here (decimal
                                   degrees).
REVISED Longitude...............  Enter revised Longitude here (decimal
                                   degrees).
REVISED MACT Code...............  Enter revised MACT Code here.
REVISED Pollutant Code..........  Enter revised Pollutant Code here.
REVISED Routine Emissions.......  Enter revised routine emissions value
                                   here (TPY).
REVISED SCC Code................  Enter revised SCC Code here.
REVISED Stack Diameter..........  Enter revised Stack Diameter here
                                   (ft).
REVISED Stack Height............  Enter revised Stack Height here (Ft).
REVISED Start Date..............  Enter revised Start Date here.
REVISED State...................  Enter revised State here.
REVISED Tribal Code.............  Enter revised Tribal Code here.
REVISED Zip Code................  Enter revised Zip Code here.
Shutdown Emissions..............  Enter total annual emissions due to
                                   shutdown events (TPY).
Shutdown Emissions Max Hourly...  Enter maximum hourly shutdown
                                   emissions here (lb/hr).

Stack Comment...................  Enter general comments about emission
                                   release points.
Startup Emissions...............  Enter total annual emissions due to
                                   startup events (TPY).
Startup Emissions Max Hourly....  Enter maximum hourly startup emissions
                                   here (lb/hr).
Year Closed.....................  Enter date facility stopped
                                   operations.
------------------------------------------------------------------------

    2. Fill in the commenter information fields for each suggested
revision (i.e., commenter name, commenter organization, commenter e-
mail address, commenter phone number, and revision comments).
    3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations, etc.).
    4. Send the entire downloaded file with suggested revisions in
Microsoft[supreg] Access format and all accompanying documentation to
Docket ID Number EPA-HQ-OAR-2004-0305 (through one of the methods
described in the ADDRESSES section of this preamble). To expedite
review of the revisions, it would also be helpful if you submitted a
copy of your revisions to the EPA directly at<EMAIL_ADDRESS>in addition
to submitting them to the docket.
    5. If you are providing comments on a facility, you need only
submit one file for that facility, which should contain all suggested
changes for all sources at that facility. We request that all data
revision comments be submitted in the form of updated Microsoft[supreg]
Access files, which are provided on the http://www.epa.gov/ttn/atw/rrisk/rtrpg.html Web page.

IX. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
action is a significant regulatory action because it raises novel legal
and policy issues. Accordingly, EPA submitted this action to the Office
of Management and Budget (OMB) for review under Executive Order 12866
and any changes made in response to OMB recommendations have been
documented in the docket for this action.

B. Paperwork Reduction Act

    The information collection requirements in this rule have been
submitted for approval to the Office of Management and Budget (OMB)
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. The
Information Collection Request (ICR) document prepared by EPA has been
assigned EPA ICR number 1856.07.
    We are proposing new paperwork requirements to the Primary Lead
Smelting source category in the form of monitoring for lead
concentrations in air and increased frequency for stack testing as
described in 40 CFR 63.1547(k) (compliance monitoring) and 40 CFR
63.1546 (stack testing). These requirements are described in section
VI.A and B. Although these are additional requirements under today's
proposed rule, they are consistent with existing monitoring and testing
currently conducted by the facility to meet MACT and SIP requirements.
Therefore, we do not believe that the additional paperwork required by
these proposed changes would constitute an undue burden to the
facility.
    We estimate one regulated entity is currently subject to subpart
TTT and will be subject to all proposed standards. This facility will
have no capital costs associated with the information collection
requirements in the proposed rule.
    The estimated recordkeeping and reporting burden after the
effective date of the proposed rule is estimated to be 1,323 labor
hours at a cost of $465,503. This estimate includes the cost of
reporting, including reading instructions, and information gathering.
Recordkeeping cost estimates include reading instructions, planning
activities, monitoring plan development, conducting compliance
monitoring, sampling and analysis and maintenance of rolling 3-month
average data. The average hours and cost per regulated entity would be
1,323 hours and $465,503 based on one facility response per year.
Burden is defined at 5 CFR 1320.3(b).
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations in 40 CFR are listed in 40 CFR part 9.
    To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, EPA has established a public docket for
this rule, which includes this ICR, under Docket ID number EPA-HQ-OAR-
2004-0305. Submit any comments related to the ICR to EPA and OMB. See
ADDRESSES section at the beginning of this notice for where to submit
comments to EPA. Send comments to OMB at the Office of Information and
Regulatory Affairs, Office of Management and Budget, 725 17th Street,
NW., Washington, DC 20503, Attention: Desk Office for EPA. Since OMB is
required to make a decision concerning the ICR between 30 and 60 days
after February 17, 2011, a comment to OMB is best assured of having its
full effect if OMB receives it by March 21, 2011. The final rule will
respond to any OMB or public comments on the information collection
requirements contained in this proposal.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute 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 organizations, and small governmental jurisdictions. For purposes
of assessing the impacts of today's proposed rule on small entities,
small entity is defined as: (1) A small business that is a small
industrial entity as defined by the Small Business Administration's
(SBA) regulations at 13 CFR 121.201; (2) a small governmental
jurisdiction that is a government of a city, county, town, school
district or special district with a population of less than 50,000; and
(3) a small organization that is any not-for-profit enterprise which is
independently owned and operated and is not dominant in its field.
    After considering the economic impacts of today's proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. This
proposed rule will not impose any requirements on small entities. This
proposed rule is currently applicable to one operating facility that
does not meet the definition of a small entity.
    We continue to be interested in the potential impacts of the
proposed rule on small entities and welcome comments on issues related
to such impacts.

D. Unfunded Mandates Reform Act

    This proposed rule does not contain a federal mandate under the
provisions of Title II of the Unfunded Mandates Reform Act of 1995
(UMRA), 2 U.S.C. 1531-1538 for State, local, or tribal governments or
the private sector. The proposed rule would not result in expenditures
of $100 million or more for State, local, and tribal governments, in
aggregate, or the private sector in any 1 year. The proposed rule
imposes no enforceable duties on any State, local or tribal governments
or the private sector. Thus, this proposed rule is not subject to the
requirements of sections 202 or 205 of the UMRA.
    This proposed rule is also not subject to the requirements of
section 203 of UMRA because it contains no regulatory requirements that
might significantly or uniquely affect small governments because it
contains no requirements that apply to such governments nor does it
impose obligations upon them.

E. Executive Order 13132: Federalism

    This proposed rule does not have federalism implications. It 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. None of the facilities subject
to this action are owned or operated by State governments, and, because
no new requirements are being promulgated, nothing in this proposal
will supersede State regulations. Thus, Executive Order 13132 does not
apply to this proposed rule.
    In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.

F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

    Subject to the Executive Order 13175 (65 FR 67249, November 9,
2000) EPA may not issue a regulation that has tribal 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 tribal governments, or
EPA consults with tribal officials early in the process of developing
the proposed regulation and develops a tribal summary impact statement.
EPA has concluded that this proposed rule will not have tribal
implications, as specified in Executive Order 13175. It will not have
substantial direct effect on tribal governments, on the relationship
between the federal government and Indian tribes, or on the
distribution of power and responsibilities between the Federal
government and Indian tribes, as specified in Executive Order 13175.
Thus, Executive Order 13175 does not apply to this action.
    EPA specifically solicits additional comment on this proposed
action from tribal officials.

G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks

    This proposed rule is not subject to Executive Order 13045 (62 FR
19885, April 23, 1997) because it is not economically significant as
defined in Executive Order 12866. However, the Agency does believe
there is a disproportionate risk to children. Modeled ambient air lead
concentrations from the one facility in this source category are in
excess of the NAAQS for lead, which was set to ``provide increased
protection for children and other at-risk populations against an array
of adverse health effects, most notably including neurological effects
in children, including neurocognitive and neurobehavioral effects.'' 73
FR 67007. However, the control measures proposed in this notice will
result in lead concentration levels that are in compliance with the
lead NAAQS, thereby mitigating the risk of adverse health effects to
children.

H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use

    This action is not a ``significant energy action'' as defined under
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR
28355, May 22, 2001), because it is not likely to have significant
adverse effect on the supply, distribution, or use of energy. This
action will not create any new requirements for sources in the energy
supply, distribution, or use sectors.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (``NTTAA''), Public Law 104-113, 12(d) (15 U.S.C. 272 note)
directs EPA to use voluntary consensus standards in its regulatory
activities unless to do so would be inconsistent with applicable law or
otherwise impractical. Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies. The NTTAA directs EPA to provide
Congress, through OMB, explanations when the Agency decides not to use
available and applicable voluntary consensus standards.
    This proposed rulemaking does not involve technical standards.
Therefore, EPA is not considering the use of any voluntary consensus
standards.

J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
federal executive policy on environmental justice. Its main provision
directs federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
    To examine the potential for any environmental justice issues that
might be associated with each source category, we evaluated the
distributions of HAP-related cancer and non-cancer risks across
different social, demographic, and economic groups within the
populations living near the facilities where these source categories
are located. The methods used to conduct demographic analyses for this
rule are described in section IV.A of the preamble for this rule. The
development of demographic analyses to inform the consideration of
environmental justice issues in EPA rulemakings is an evolving science.
The EPA offers the demographic analyses in today's rulemaking as
examples of how such analyses might be developed to inform such
consideration, and invites public comment on the approaches used and
the interpretations made from the results, with the hope that this will
support the refinement and improve utility of such analyses for future
rulemakings.
    In the case of Primary Lead Processing, we focused on populations
within 50 km of the one facility in this source category with emission
sources subject to the MACT standard. More specifically, for these
populations we

evaluated exposures to HAP which could result in cancer risks of 1-in-1
million or greater, or population exposures to ambient air lead
concentrations above the level of the NAAQS for lead. We compared the
percentages of particular demographic groups within the focused
populations to the total percentages of those demographic groups
nationwide. The results of this analysis are documented in section
V.B.1 (see Table 6), as well as in a technical report located in the
docket for this rulemaking. In brief, although our analyses show that
there is the potential for adverse environmental and human health
effects from emissions of lead, it does not indicate any significant
potential for disparate impacts to the specific demographic groups
analyzed (see section V.B.1). Notably however, the proposed rule would
require additional control measures to address the identified
environmental and health risks and would therefore, decrease risks to
any populations exposed to these sources.

List of Subjects in 40 CFR Part 63

    Environmental protection, Air pollution control, Reporting and
recordkeeping requirements, Lead.

    Dated: January 31, 2011.
Lisa P. Jackson,
Administrator.

    For reasons set out in the preamble, title 40, chapter I, of the
Code of Federal Regulations is proposed to be amended:

PART 63--[AMENDED]

    1. The authority citation for part 63 continues to read as follows:

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

    2. Section 63.1541 is revised to read as follows:

Sec.  63.1541  Applicability.

    (a) The provisions of this subpart apply to any facility engaged in
producing lead metal from ore concentrates. The category includes, but
is not limited to, the following smelting processes: Sintering,
reduction, preliminary treatment, refining and casting operations,
process fugitive sources, and fugitive dust sources. The sinter process
includes an updraft or downdraft sintering machine. The reduction
process includes the blast furnace, electric smelting furnace with a
converter or reverberatory furnace, and slag fuming furnace process
units. The preliminary treatment process includes the drossing kettles
and dross reverberatory furnace process units. The refining process
includes the refinery process unit. The provisions of this subpart do
not apply to secondary lead smelters, lead refiners, or lead remelters.
    (b) Table 1 of this subpart specifies the provisions of subpart A
of this part that apply and those that do not apply to owners and
operators of primary lead processors.
    3. Section 63.1542 is amended by:
    a. Adding in alphabetical order definitions for ``Affirmative
defense,'' ``Lead refiner,'' ``Lead remelter,'' ``Primary lead
processor,'' and ``Secondary lead smelter''.
    b. Removing the definition for ``Primary lead smelter''.
    c. Revising the definitions for ``Fugitive dust source,'' ``Furnace
area,'' ``Malfunction,'' ``Materials storage and handling area,''
``Plant roadway,'' ``Process fugitive source,'' ``Refining and casting
area,'' Sinter machine area,'' and ``Tapping location''.

Sec.  63.1542  Definitions.

* * * * *
    Affirmative defense means, in the context of an enforcement
proceeding, a response or defense put forward by a defendant, regarding
which the defendant has the burden of proof, and the merits of which
are independently and objectively evaluated in a judicial or
administrative proceeding.
* * * * *
    Fugitive dust source means a stationary source of hazardous air
pollutant emissions at a primary lead processor resulting from the
handling, storage, transfer, or other management of lead-bearing
materials where the source is not part of a specific process, process
vent, or stack. Fugitive dust sources include roadways, storage piles,
materials handling transfer points, and materials transport areas.
    Furnace area means any area of a primary lead processor in which a
blast furnace or dross furnace is located.
    Lead refiner means any facility that refines lead metal that is not
located at a primary lead processor.
    Lead remelter means any facility that remelts lead metal that is
not located at a primary lead processor.
    Malfunction means any sudden, infrequent, and not reasonably
preventable failure of air pollution control and monitoring equipment,
process equipment, or a process to operate in a normal or usual manner
which causes, or has the potential to cause, the emission limitations
in an applicable standard to be exceeded. Failures that are caused in
part by poor maintenance or careless operation are not malfunctions.
    Materials storage and handling area means any area of a primary
lead processor in which lead-bearing materials (including ore
concentrate, sinter, granulated lead, dross, slag, and flue dust) are
stored or handled between process steps, including areas in which
materials are stored in piles, bins, or tubs, and areas in which
material is prepared for charging to a sinter machine or smelting
furnace or other lead processing operation.
* * * * *
    Plant roadway means any area of a primary lead processor that is
subject to vehicle traffic, including traffic by forklifts, front-end
loaders, or vehicles carrying ore concentrates or cast lead ingots.
Excluded from this definition are employee and visitor parking areas,
provided they are not subject to traffic by vehicles carrying lead-
bearing materials.
    Primary lead processor means any facility engaged in the production
of lead metal from lead sulfide ore concentrates through the use of
pyrometallurgical or other techniques.
    Process fugitive source means a source of hazardous air pollutant
emissions at a primary lead processor that is associated with lead
smelting, processing or refining but is not the primary exhaust stream
and is not a fugitive dust source. Process fugitive sources include
sinter machine charging locations, sinter machine discharge locations,
sinter crushing and sizing equipment, furnace charging locations,
furnace taps, and drossing kettle and refining kettle charging or
tapping locations.
    Refining and casting area means any area of a primary lead
processor in which drossing or refining operations occur, or casting
operations occur.
    Secondary lead smelter means any facility at which lead-bearing
scrap material, primarily, but not limited to, lead-acid batteries, is
recycled into elemental lead or lead alloys by smelting.
* * * * *
    Sinter machine area means any area of a primary lead processor
where a sinter machine, or sinter crushing and sizing equipment is
located.
* * * * *
    Tapping location means the opening through which lead and slag are
removed from the furnace.
    4. Section 63.1543 is revised to read as follows:

Sec.  63.1543  Standards for process and process fugitive sources.

    (a) No owner or operator of any existing, new, or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds in excess of 0.22

pounds per ton of lead metal produced from the aggregation of emissions
discharged from air pollution control devices used to control emissions
at primary lead processing facilities, including the sources listed in
paragraphs (a)(1) through (a)(10) of this section.
    (1) Sinter machine;
    (2) Blast furnace;
    (3) Dross furnace;
    (4) Dross furnace charging location;
    (5) Blast furnace and dross furnace tapping location;
    (6) Sinter machine charging location;
    (7) Sinter machine discharge end;
    (8) Sinter crushing and sizing equipment;
    (9) Sinter machine area; and
    (10) Refining and casting, and furnace area.
    (b) No owner or operator of any existing, new, or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds in excess of 0.91 tons per year from the
air pollution control devices used to control emissions from furnace
area and refining and casting operations.
    (c) The process fugitive sources listed in paragraphs (a)(4)
through (a)(8) of this section must be equipped with a hood and must be
ventilated to a baghouse or equivalent control device. The hood design
and ventilation rate must be consistent with American Conference of
Governmental Industrial Hygienists recommended practices.
    (d) The sinter machine area must be enclosed in a building that is
ventilated to a baghouse or equivalent control device at a rate that
maintains a positive in-draft through any doorway opening.
    (e) Except as provided in paragraph (f) of this section, following
the initial tests to demonstrate compliance with paragraphs (a)and (b)
of this section, the owner or operator of a primary lead processor must
conduct compliance tests for lead compounds on an quarterly basis (no
later than 100 days following any previous compliance test).
    (f) If the 12 most recent compliance tests demonstrate compliance
with the emission limit specified in paragraphs (a) and (b) of this
section, the owner or operator of a primary lead processor shall be
allowed up to 12 calendar months from the last compliance test to
conduct the next compliance test for lead compounds.
    (g) The owner or operator of a primary lead processor must maintain
and operate each baghouse used to control emissions from the sources
listed in paragraphs (a)(1) through (a)(10) of this section such that
the alarm on a bag leak detection system required under Sec.
63.1547(c)(8) does not sound for more than five percent of the total
operating time in a 6-month reporting period.
    (h) The owner or operator of a primary lead processor must record
the date and time of a bag leak detection system alarm and initiate
procedures to determine the cause of the alarm according to the
corrective action plan required under Sec.  63.1547(f) within 1 hour of
the alarm. The cause of the alarm must be corrected as soon as
practicable.
    (i) At all times, the owner or operator must operate and maintain
any affected source, including associated air pollution control
equipment and monitoring equipment, in a manner consistent with safety
and good air pollution control practices for minimizing emissions.
Determination of whether such operation and maintenance procedures are
being used will be based on information available to the Administrator
which may include, but is not limited to, monitoring results, review of
operation and maintenance procedures, review of operation and
maintenance records, and inspection of the source.
    5. Section 63.1544 is revised to read as follows:

Sec.  63.1544  Standards for fugitive dust sources.

    (a) No owner or operator of any existing, new or reconstructed
primary lead processor shall discharge or cause to be discharged into
the atmosphere lead compounds that cause the concentration of lead in
air to exceed 0.15 [micro]g/m\3\ on a 3-month rolling average measured
at locations approved by the Administrator.
    (b) At all times, the owner or operator must operate and maintain
any affected source, including associated air pollution control
equipment and monitoring equipment, in a manner consistent with safety
and good air pollution control practices for minimizing emissions.
Determination of whether such operation and maintenance procedures are
being used will be based on information available to the Administrator
which may include, but is not limited to, monitoring results, review of
operation and maintenance procedures, review of operation and
maintenance records, and inspection of the source.
    6. Section 63.1545 is revised to read as follows:

Sec.  63.1545  Compliance dates.

    (a) Each owner or operator of an existing primary lead processor
must achieve compliance with the requirements of this subpart no later
than [DATE TWO YEARS FROM PUBLICATION OF THE FINAL RULE IN THE FEDERAL
REGISTER].
    (b) Each owner or operator of a new primary lead processor must
achieve compliance with the requirements of this subpart no later than
[DATE 60 DAYS AFTER PUBLICATION OF THE FINAL RULE IN THE FEDERAL
REGISTER] or startup, whichever is later.
    7. Section 63.1546 is revised to read as follows:

Sec.  63.1546  Performance testing.

    (a) The following procedures must be used to determine quarterly
compliance with the emissions standard for lead compounds under Sec.
63.1543(a) and (b) for existing sources:
    (1) Each owner or operator of existing sources listed in Sec.
63.1543(a)(1) through (10) must determine the lead compound emissions
rate, in units of pounds of lead per hour according to the following
test methods in appendices of part 60 of this chapter:
    (i) Method 1 to appendix A-1 of 40 CFR part 60 must be used to
select the sampling port location and the number of traverse points.
    (ii) Methods 2 and 2F of appendix A-1 and Method 2G of appendix A-2
of 40 CFR part 60 must be used to measure volumetric flow rate.
    (iii) Methods 3, 3A, 3B of appendix A-2 of 40 CFR part 60 must be
used for gas analysis.
    (iv) Method 4 of appendix A-3 of 40 CFR part 60 must be used to
determine moisture content of the stack gas.
    (v) Method 12 of appendix A-5 or Method 29 of appendix A-8 of 40
CFR part 60 must be used to determine lead emissions rate of the stack
gas.
    (2) A performance test shall consist of at least three runs. For
each test run with Method 12 of appendix A-5 or Method 29 of appendix
A-8 of 40 CFR part 60, the minimum sample time must be 60 minutes and
the minimum volume must be 1 dry standard cubic meter (35 dry standard
cubic feet).
    (3) Performance tests shall be completed quarterly, once every 3
months, to determine compliance.
    (4) The lead emission rate in pounds per quarter is calculated by
multiplying the quarterly lead emission rate in pounds per hour by the
quarterly plant operating time, in hours as shown in Equation 1:

[GRAPHIC] [TIFF OMITTED] TP17FE11.001

Where:

EPb = quarterly lead emissions, pounds per quarter;

ERPb = quarterly lead emissions rate, pounds per hour;
and
QPOT = quarterly plant operating time, hours per quarter.

    (5) The lead production rate, in units of tons per quarter, must be
determined based on production data for the previous quarter according
to the procedures detailed in paragraphs (a)(5)(i) through (iv) of this
section:
    (i) Total lead products production multiplied by the fractional
lead content must be determined in units of tons.
    (ii) Total copper matte production multiplied by the fractional
lead content must be determined in units of tons.
    (iii) Total copper speiss production multiplied by the fractional
lead content must be determined in units of tons.
    (iv) Total quarterly lead production must be determined by summing
the values obtained in paragraphs (a)(5)(i) through (a)(5)(iii) of this
section.
    (6) To determine compliance with the production-based lead compound
emission rate in Sec.  63.1543(a), the quarterly production-based lead
compound emission rate, in units of pounds of lead emissions per ton of
lead produced, is calculated as shown in Equation 2 by dividing lead
emissions by lead production.

[GRAPHIC] [TIFF OMITTED] TP17FE11.002

Where:
CEPb = quarterly production-based lead compound emission
rate, in units of pounds of lead emissions per ton of lead produced;
EPb = quarterly lead emissions, pounds per quarter; and
PPb = quarterly lead production, tons per quarter.

    (7) To determine quarterly compliance with the emissions standard
for lead compounds under Sec.  63.1543(b), sum the lead compound
emission rates for the current and previous three quarters for the
sources in Sec.  63.1543 (a)(10) to determine compliance with Sec.
63.1543(b), as determined in accordance with paragraphs (a)(1) through
(a)(4) of this section.
    (b) Owner and operators must perform an initial compliance test to
demonstrate compliance with the sinter building in-draft requirements
of Sec.  63.1543(d) at each doorway opening in accordance with
paragraphs (b)(1) through (b)(4) of this section.
    (1) Use a propeller anemometer or equivalent device.
    (2) Determine doorway in-draft by placing the anemometer in the
plane of the doorway opening near its center.
    (3) Determine doorway in-draft for each doorway that is open during
normal operation with all remaining doorways in their customary
position during normal operation.
    (4) Do not determine doorway in-draft when ambient wind speed
exceeds 2 meters per second.
    (c) Performance tests shall be conducted under such conditions as
the Administrator specifies to the owner or operator based on
representative performance of the affected source for the period being
tested. Upon request, the owner or operator shall make available to the
Administrator such records as may be necessary to determine the
conditions of performance tests.
    8. Section 63.1547 is revised to read as follows:

Sec.  63.1547  Monitoring requirements.

    (a) Owners and operators of primary lead processors must prepare,
and at all times operate according to, a standard operating procedures
manual that describes in detail the procedures for inspection,
maintenance, and bag leak detection and corrective action for all
baghouses that are used to control process, process fugitive, or
fugitive dust emissions from any source subject to the lead emission
standards in Sec. Sec.  63.1543 and 63.1544, including those used to
control emissions from general ventilation systems.
    (b) The standard operating procedures manual for baghouses required
by paragraph (a) of this section must be submitted to the Administrator
or delegated authority for review and approval.
    (c) The procedures specified in the standard operating procedures
manual for inspections and routine maintenance must, at a minimum,
include the requirements of paragraphs (c)(1) through (c)(8) of this
section.
    (1) Weekly confirmation that dust is being removed from hoppers
through visual inspection or equivalent means of ensuring the proper
functioning of removal mechanisms.
    (2) Daily check of compressed air supply for pulse-jet baghouses.
    (3) An appropriate methodology for monitoring cleaning cycles to
ensure proper operation.
    (4) Monthly check of bag cleaning mechanisms for proper functioning
through visual inspection or equivalent means.
    (5) Quarterly visual check of bag tension on reverse air and
shaker-type baghouses to ensure that bags are not kinked (kneed or
bent) or laying on their sides. Such checks are not required for
shaker-type baghouses using self-tensioning (spring loaded) devices.
    (6) Quarterly confirmation of the physical integrity of the
baghouse through visual inspection of the baghouse interior for air
leaks.
    (7) Quarterly inspection of fans for wear, material buildup, and
corrosion through visual inspection, vibration detectors, or equivalent
means.
    (8) Except as provided in paragraph (h) of this section, continuous
operation of a bag leak detection system.
    (d) The procedures specified in the standard operating procedures
manual for maintenance must, at a minimum, include a preventative
maintenance schedule that is consistent with the baghouse
manufacturer's instructions for routine and long-term maintenance.
    (e) The bag leak detection system required by paragraph (c)(8) of
this section must meet the specifications and requirements of (e)(1)
through (e)(8) of this section.
    (1) The bag leak detection system must be certified by the
manufacturer to be capable of detecting particulate matter emissions at
concentrations of 10 milligram per actual cubic meter (0.0044 grains
per actual cubic foot) or less.
    (2) The bag leak detection system sensor must provide output of
relative particulate matter loadings, and the owner or operator must
continuously record the output from the bag leak detection system.
    (3) The bag leak detection system must be equipped with an alarm
system that will sound when an increase in relative particulate loading
is detected over a preset level, and the alarm must be located such
that it can be heard or otherwise determined by the appropriate plant
personnel.
    (4) Each bag leak detection system that works based on the
triboelectric effect must be installed, calibrated, and maintained in a
manner consistent with guidance provided in the U.S. Environmental
Protection Agency guidance document ''Fabric Filter Bag Leak Detection
Guidance'' (EPA-454/R-98-015). Other bag leak detection systems must be
installed, calibrated, and maintained in a manner consistent with the
manufacturer's written specifications and recommendations.
    (5) The initial adjustment of the system must, at a minimum,
consist of establishing the baseline output by adjusting the
sensitivity (range) and the averaging period of the device, and
establishing the alarm set points and the alarm delay time.
    (6) Following initial adjustment, the owner or operator must not
adjust the sensitivity or range, averaging period, alarm set points, or
alarm delay time, except as detailed in the approved SOP required under
paragraph (a) of this

section. In no event shall the sensitivity be increased by more than
100 percent or decreased more than 50 percent over a 365-day period
unless a responsible official certifies that the baghouse has been
inspected and found to be in good operating condition.
    (7) For negative pressure, induced air baghouses, and positive
pressure baghouses that are discharged to the atmosphere through a
stack, the bag leak detector must be installed downstream of the
baghouse and upstream of any wet acid gas scrubber.
    (8) Where multiple detectors are required, the system's
instrumentation and alarm may be shared among detectors.
    (f) The standard operating procedures manual required by paragraph
(a) of this section must include a corrective action plan that
specifies the procedures to be followed in the event of a bag leak
detection system alarm. The corrective action plan must include at a
minimum, procedures to be used to determine the cause of an alarm, as
well as actions to be taken to minimize emissions, which may include,
but are not limited to, the following.
    (1) Inspecting the baghouse for air leaks, torn or broken bags or
filter media, or any other condition that may cause an increase in
emissions.
    (2) Sealing off defective bags or filter media.
    (3) Replacing defective bags or filter media, or otherwise
repairing the control device.
    (4) Sealing off a defective baghouse compartment.
    (5) Cleaning the bag leak detection system probe, or otherwise
repairing or maintaining the bag leak detection system.
    (6) Shutting down the process producing the particulate emissions.
    (g) The percentage of total operating time the alarm on the bag
leak detection system sounds in a 6-month reporting period must be
calculated in order to determine compliance with the five percent
operating limit in Sec.  63.1543(h). The percentage of time the alarm
on the bag leak detection system sounds must be determined according to
paragraphs (g)(1) through (g)(3) of this section.
    (1) For each alarm where the owner or operator initiates procedures
to determine the cause of an alarm within 1 hour of the alarm, 1 hour
of alarm time must be counted.
    (2) For each alarm where the owner or operator does not initiate
procedures to determine the cause of the alarm within 1 hour of the
alarm, alarm time will be counted as the actual amount of time taken by
the owner or operator to initiate procedures to determine the cause of
the alarm.
    (3) The percentage of time the alarm on the bag leak detection
system sounds must be calculated as the ratio of the sum of alarm times
to the total operating time multiplied by 100.
    (h) Baghouses equipped with HEPA filters as a secondary filter used
to control process or process fugitive sources subject to the lead
emission standards in Sec.  63.1543 are exempt from the requirement in
paragraph (c)(8) of this section to be equipped with a bag leak
detector. The owner or operator of an affected source that uses a HEPA
filter must monitor and record the pressure drop across the HEPA filter
system daily. If the pressure drop is outside the limit(s) specified by
the filter manufacturer, the owner or operator must take appropriate
corrective measures, which may include, but not be limited to, the
following:
    (1) Inspecting the filter and filter housing for air leaks and torn
or broken filters.
    (2) Replacing defective filter media, or otherwise repairing the
control device.
    (3) Sealing off a defective control device by routing air to other
comparable control devices.
    (4) Shutting down the process producing the particulate emissions.
    (i) Owners and operators must monitor sinter machine building in-
draft to demonstrate continued compliance with the operating standard
specified in Sec.  63.1543(d) in accordance with either paragraph
(i)(1), (i)(2), or (i)(3) of this section.
    (1) Owners and operators must check and record on a daily basis
doorway in-draft at each doorway in accordance with the methodology
specified in Sec.  63.1546(b).
    (2) Owners and operators must establish and maintain baseline
ventilation parameters which result in a positive in-draft according to
paragraphs (i)(2)(i) through (i)(2)(iv) of this section.
    (i) Owners and operators must install, calibrate, maintain, and
operate a monitoring device that continuously records the volumetric
flow rate through each separately ducted hood; or install, calibrate,
maintain, and operate a monitoring device that continuously records the
volumetric flow rate at the control device inlet of each exhaust system
ventilating the building. The flow rate monitoring device(s) can be
installed in any location in the exhaust duct such that reproducible
flow rate measurements will result. The flow rate monitoring device(s)
must have an accuracy of plus or minus 10 percent over the normal
process operating range and must be calibrated according to
manufacturer's instructions.
    (ii) During the initial demonstration of sinter building in-draft,
and at any time the owner or operator wishes to re-establish the
baseline ventilation parameters, the owner or operator must
continuously record the volumetric flow rate through each separately
ducted hood, or continuously record the volumetric flow rate at the
control device inlet of each exhaust system ventilating the building
and record exhaust system damper positions. The owner or operator must
determine the average volumetric flow rate(s) corresponding to the
period of time the in-draft compliance determinations are being
conducted.
    (iii) The owner or operator must maintain the volumetric flow
rate(s) at or above the value(s) established during the most recent in-
draft determination at all times the sinter machine is in operation.
Volumetric flow rate(s) must be calculated as a 15-minute average.
    (iv) If the volumetric flow rate is monitored at the control device
inlet, the owner or operator must check and record damper positions
daily to ensure they are in the positions they were in during the most
recent in-draft determination.
    (3) An owner or operator may request an alternative monitoring
method by following the procedures and requirements in Sec.  63.8(f) of
the General Provisions.
    (j) Each owner or operator of new or modified sources listed under
Sec.  63.1543 (a)(1) through (a)(10) must install, calibrate, maintain,
and operate a continuous emission monitoring system (CEMS) for
measuring lead emissions and a continuous emission rate monitoring
system (CERMS) subject to Performance Specification 6 of Appendix B to
part 60.
    (1) Each owner or operator of a source subject to the emissions
limits for lead compounds under Sec.  63.1543(a) and (b) must install a
CEMS for measuring lead emissions within 180 days of promulgation of
performance specifications for lead CEMS.
    (i) Prior to promulgation of performance specifications for CEMS
used to measure lead concentrations, an owner or operator must use the
procedure described in Sec.  63.1546(a)(1) through (a)(7) of this
section to determine compliance.
    (ii) [Reserved]
    (2) If a CEMS used to measure lead emissions is applicable, the
owner or operator must install a CERMS with a sensor in a location that
provides representative measurement of the exhaust gas flow rate at the
sampling

location of the CEMS used to measure lead emissions, taking into
account the manufacturer's recommendations. The flow rate sensor is
that portion of the system that senses the volumetric flow rate and
generates an output proportional to that flow rate.
    (i) The CERMS must be designed to measure the exhaust gas flow rate
over a range that extends from a value of at least 20 percent less than
the lowest expected exhaust flow rate to a value of at least 20 percent
greater than the highest expected exhaust gas flow rate.
    (ii) The CERMS must be equipped with a data acquisition and
recording system that is capable of recording values over the entire
range specified in paragraph (b)(2)(i) of this section.
    (iii) Each owner or operator must perform an initial relative
accuracy test of the CERMS in accordance with the applicable
Performance Specification in Appendix B to part 60 of the chapter.
    (iv) Each owner or operator must operate the CERMS and record data
during all periods of operation of the affected facility including
periods of startup, shutdown, and malfunction, except for periods of
monitoring system malfunctions, repairs associated with monitoring
system malfunctions, and required monitoring system quality assurance
or quality control activities (including, as applicable, calibration
checks and required zero and span adjustments.
    (3) Each owner or operator must calculate the lead emissions rate
in tons per year by summing all hours of CEMS data for a year to
determine compliance with 63.1543(b).
    (i) When the CERMS are unable to provide quality assured data the
following applies:
    (A) When data are not available for periods of up to 48 hours, the