to POM emissions from the one currently operating Soderberg facility.
The highest MIR due to actual emissions from prebake facilities was
estimated to be up to 20 in one million; the next highest MIR for an
operating prebake facility is estimated to be up to 6 in one million.
The total estimated cancer incidence from this source category based on
actual emission levels is 0.005 excess cancer cases per year or one
case in every 200 years, with emissions of POM contributing
approximately 99 percent to this cancer incidence. In addition, we note
that approximately 41,000 people are estimated to have cancer risks
greater than 1 in one million, and approximately 900 people are
estimated to have risks greater than 10 in one million. When
considering the risks associated with MACT-allowable emissions, the MIR
could be up to 100 in one million if the Columbia Falls facility (a
Soderberg type facility) were to resume its primary aluminum operations
(see note 4 on Table 6). The MIR based on allowable emissions from the
one currently operating Soderberg facility (Massena East facility) was
up to 50 in one million. The highest MIR based on allowable emissions
from any of the prebake facilities was up to 30 in one million.
---------------------------------------------------------------------------

    \20\ Most all POM emitted by this source category are PAHs.
---------------------------------------------------------------------------

    The maximum modeled chronic non-cancer TOSHI value is 0.4 based on
actual emissions, driven primarily by HF emissions. When considering
MACT allowable emissions, the maximum chronic non-cancer TOSHI value
could be up to 0.6. For this source category, there were two HAP that
had relevant acute health effect screening values: Carbonyl sulfide
(COS) and hydrofluoric acid (HF). Acute health effect screening is
performed using actual emissions data. The Columbia Falls facility has
not operated in about 2 years and has not operated at capacity since
about 1999. Therefore, suitable actual emission data was not available
for this facility and its acute health effects are not included in this
discussion. Further, the carbon-only prebake anode production facility
does not emit COS or HF. Therefore, this discussion addresses the acute
health effects of only the 13 remaining facilities subject to this
NESHAP. With respect to COS, we did not find any potential for acute
health concerns for the 13 facilities based on their actual emissions.
However, HF emissions did not screen out with respect to potential
acute health effects. The highest refined worst-case HQ for HF based on
a REL is 10, based on an AEGL-1 is 4, and based on an ERPG-1 is 2.
Moreover, 8 of the 13 facilities show the potential for worst-case
acute HQ values greater than 1 based on the REL, 4 of the 13 facilities
show the potential for worst-case acute HQ values greater than 1 based
on the AEGL-1 and 4 of the 13 facilities show the potential for worst-
case acute HQ values greater than or equal to 1 based on the ERPG-
1.\21\ Nevertheless, it is

important to note that all the worst-case acute HQs are based on
conservative assumptions (e.g., worst-case meteorology coinciding with
peak short-term one-hour emissions from each emission point, with a
person located at the point of maximum concentration during that hour).
---------------------------------------------------------------------------

    \21\ Individual facility acute HQ values for all facilities can
be found in Appendix 5, Table 4, of the risk assessment document
that is included in the docket for this proposed rulemaking. Acute
HQ values exceeding a value of 1 based on the REL were as follows:
10, 10, 9, 9, 5, 3, 2 and 2. Acute HQ values greater than a value of
1 based on the AEGL-1 were as follows: 4, 4, 3 and 3. Acute HQ
values greater than or equal to a value of 1 based on the ERPG-1
were as follows: 2, 2, 1 and 1.
---------------------------------------------------------------------------

    In addition to the analyses presented above, to screen for
potential multi-pathway effects from emissions of POM, we compared the
estimated actual PAH emission rates from 14 facilities in this source
category to the multi-pathway screening rate for PAHs described in
section III.B. Results of this worst-case screen estimate that actual
PAH emissions from all 14 facilities exceed the PAH multi-pathway
screening rate. With respect to these exceedances of the worst-case
multi-pathway screening rate for PAHs, we note that this only indicates
the potential for multi-pathway-related cancer risks of concern from
PAHs. Moreover, due to data limitations, we were not able to refine our
multi-pathway analysis beyond the screening assessment. Thus, we note
that these results are biased high for purposes of screening and are
subject to significant uncertainties. As such, they do not necessarily
indicate that multi-pathway risks from POM are significant, only that
we cannot rule out the possibility that they might be significant.

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

1. Risk Acceptability
    As noted in section III.C of this preamble, we weigh all health
risk factors in our risk acceptability determination, including the
MIR, the numbers of persons in various risk ranges, cancer incidence,
the maximum noncancer HI, the maximum acute noncancer hazard, the
extent of noncancer risks, the potential for adverse environmental
effects, distribution of risks in the exposed population, and risk
estimation uncertainties (54 FR 38044, September 14, 1989).
    For the Primary Aluminum Reduction source category, the risk
analysis we performed indicates that the cancer risk to the individual
most exposed due to actual emissions is well below 100 in one million,
and the cancer incidence is low (1 case in every 200 years). The
potential risks due to allowable emissions are higher with an estimated
MIR of up to 100 in one million which is the presumptive upper limit of
acceptable risk.
    With regard to noncancer risks, the analysis indicates that chronic
noncancer health risks are negligible due to both actual and allowable
emissions. The assessment of potential acute noncancer effects
(described in the previous section) suggests that there may be
potential for some acute risks due to HF emissions with worst-case HQs
up to 10 (based on the REL). In characterizing the potential for acute
noncancer impacts of concern, it is important to remember the upward
bias of these worst-case exposure estimates and to consider the results
along with the rather large uncertainties related to the emissions
estimates and screening methodology.
    With regard to multi-pathway exposures and risks, results of the
screening analysis indicate that actual PAH emissions from all the
facilities exceed the worst-case multi-pathway screening rate for PAHs,
indicating the potential for possible multi-pathway-related cancer
risks of concern from PAHs. We note that these screening results do not
necessarily indicate that significant multi-pathway risks actually
exist at primary aluminum facilities, only that we cannot rule them out
as a possibility.
    Overall, in determining whether risk is acceptable, we considered
all the available health risk information, as described above. In this
case, because the MIRs due to actual emissions are well below 100-in-1
million risk, and since the one facility that could pose possible risks
due to allowable emissions of up to 100 in one million is not
operating, and because a number of other factors indicate relatively
low risk concern (e.g., low cancer incidence and low potential for
chronic noncancer risks), and given the conservative, worst-case
screening level characteristics of the acute and multi-pathway
assessments, and various uncertainties, we are proposing to determine
that the risks due to HAP emissions from this source category are
acceptable.
2. Ample Margin of Safety Analysis
    We next considered whether the existing MACT standard provides an
ample margin of safety (AMOS). Under the ample margin of safety
analysis, we evaluate the cost and feasibility of available control
technologies and other measures (including the controls, measures and
costs reviewed under the technology review) that could be applied in
this source category to further reduce the risks (or potential risks)
due to emissions of HAP identified in our risk assessment, along with
all of the health risks and other health information considered in the
risk acceptability determination described above.
    First, we evaluated the feasibility to reduce the potential risks
due to allowable POM emissions from Soderberg facilities. As described
above, the potential cancer MIR from Soderberg facilities is estimated
to be up to 100 in one million due to allowable emissions. These risks
are driven by POM emissions from a Soderberg facility within the
vertical stud Soderberg (VSS2) subcategory. The current emissions limit
(from the 2005 NESHAP amendments) for POM from potlines in this VSS2
subcategory is 2.85 kg of POM per Mg of Aluminum produced (2.85 kg/Mg,
or 5.7 lbs/ton). Based on site-specific emissions data submitted by the
company in early 2008 for this facility, the estimated actual emissions
from this facility were about 2 lbs/ton during the most recent years of
operation (see Document EPA-HQ-OAR-2002-0031-0029, which is available
in the docket for this rulemaking).
    After considering variability in emissions, which is appropriate
for establishing MACT limits (as described in section III.A above), we
calculated, using a 99% upper prediction level approach, that an
emissions limit of 3.8 lbs/ton could be achieved by this facility
without any additional controls and therefore no additional costs. This
would result in a reduction of approximately 33 percent for the
allowable emissions from VSS2 potlines, and would reduce the potential
cancer MIR due to allowable emissions to about 70 in one million. We
also evaluated potential controls to reduce these risks further (such
as requiring wet roof scrubbers). We determined that these controls
would be quite costly (approximately $4 million per ton of organic
HAP), with estimated capital costs of about $40 million for this
facility, and would only achieve about an additional 9.6 tons of HAP
per year (30 percent) reduction in POM emissions. These controls and
costs are described in more detail below.
    We also evaluated the POM emissions from the one operating
Soderberg facility (which is in the HSS subcategory) as part of our
AMOS analyses. Based on the risk assessment, we estimated that this
facility posed a cancer MIR of up to 30 in one million based on actual
emissions and an MIR of up to 50 in one million based on allowable
emissions. The current

emissions limit for POM from potlines for this HSS subcategory is 2.35
kg/Mg (or 4.7 lbs/ton). Based on site specific emissions data for this
facility, the actual emissions from this facility are estimated to be
about 1.5 lbs/ton. After considering variability in emissions, we
determined that an emissions limit of 3.0 lbs/ton could be achieved by
this facility with no additional controls and, therefore, no additional
costs. This would result in a reduction of approximately 36 percent for
the allowable emissions from these HSS potlines, and would reduce the
potential cancer MIR due to allowable emissions from this facility to
about 30 in one million.
    We identified wet roof scrubbers as one possible control technology
that could be applied to further reduce allowable and actual emissions
of POM from potlines, to reduce the cancer risks due to actual and
allowable POM emissions, and to reduce the potential risks due to
multi-pathway exposures to POM. One facility in the source category
currently has this type of scrubber. These controls can also be used to
reduce HF emissions and, thus, would reduce the potential for acute
noncancer risks. However, the costs for these controls are high. For
example, we estimate that the capital costs for the typical facility
would be more than $40 million, with annualized costs of $13 million.
Industry wide this would result in total capital costs of over $400
million, with estimated annualized costs of over $150 million. These
controls would achieve reductions of secondary emissions of about 30 to
50 percent. Given the high costs (estimated at approximately $140,000
per ton of HAP) and relatively low emissions and risk reductions, we
propose that it is not appropriate or necessary to establish these
additional controls under 112(f)(2). Therefore, based our AMOS
analysis, we are proposing under section 112(f)(2) of the CAA to lower
the POM emissions limit for VSS2 potlines from 5.7 to 3.8 lbs/ton and
to lower the POM limit for HSS potlines from 4.7 to 3.0 lbs/ton.
Pursuant to CAA section 112(f)(4), we are proposing that these changes
apply 90 days after the effective date of this rulemaking. We did not
identify any other cost-effective controls to further reduce HAP
emissions for this source category under the AMOS analyses.
    In accordance with the approach established in the Benzene NESHAP,
the EPA weighed all health risk measures and information considered in
the risk acceptability determination, along with the costs and economic
impacts of emissions controls, technological feasibility, uncertainties
and other relevant factors in proposing our ample margin of safety
determination. Considering the health risk information and the costs of
the options identified, we propose that the existing MACT standards,
along with the proposed lower POM limits for potlines at Soderberg
facilities (VSS2 and HSS subcategories) described above, will provide
an ample margin of safety to protect public health.
    Pursuant to CAA section 112(f)(4), we are proposing that these
changes (i.e., lower emission limits for potlines at Soderberg
facilities) apply 90 days after the effective date of this rulemaking.
See CAA section 112(f)(4)(A).
    Nevertheless, we solicit comment and information on the
feasibility, costs and appropriateness of any additional controls or
options to further reduce the potential risks due to emissions of HAP,
especially POM and HF.

D. What are the results and proposed decisions based on our technology
review?

    As described above, dry alumina scrubbers (with baghouses) are the
typical controls used to minimize primary emissions of HF and POM from
the potlines. However, some facilities use wet scrubbers and ESPs to
control these emissions. The MACT control technology typically used for
anode bake furnaces is also a dry alumina scrubber, and a capture
system vented to a dry coke scrubber is used for control of paste
production plants. These facilities further reduce HAP emissions from
anode bake furnaces by implementation of certain practices during
periods of startup (e.g., development of an anode bake furnace startup
schedule, operation of the associated control system(s) within normal
parametric limits prior to the startup of the anode bake furnace). To
further control potline secondary emissions, one facility has wet roof
scrubbers to get additional control of HF and POM. As described in the
AMOS section above, it would be quite costly to require wet roof
scrubbers on other facilities.
    Overall, based on our technology review, we determined that there
have been no developments in practices, processes, and control
technologies that would be considered feasible and cost-effective to
apply to this source category since promulgation of the Primary
Aluminum Reduction Plant NESHAP, other than the anode bake furnace
startup practices mentioned above. We propose to modify the MACT
requirements for anode bake furnaces to include implementation of the
startup practices mentioned above. Further, based on an analysis of
recent emissions data, we believe that the practices, processes and
control technologies currently in use by this source category allow for
a reduction in the POM emission limits for Soderberg potlines (please
refer to the ample margin of safety analysis in section IV.C.2 of this
preamble).
    Additional details regarding these analyses can be found in the
following technical document for this action which is available in the
docket: Draft Technology Review for the Primary Aluminum Reduction
Plant Source Category.

E. What other actions are we proposing?

1. Startup, Shutdown and Malfunctions
    The United States Court of Appeals for the District of Columbia
Circuit vacated portions of two provisions in the EPA's CAA section 112
regulations governing the emissions of HAP during periods of startup,
shutdown and malfunction (SSM). Sierra Club v. EPA, 551 F.3d 1019 (DC
Cir. 2008), cert. denied, 130 S. Ct. 1735 (U.S. 2010). Specifically,
the Court vacated the SSM exemption contained in 40 CFR 63.6(f)(1) and
40 CFR 63.6(h)(1), that are part of a regulation, commonly referred to
as the ``General Provisions Rule,'' that the EPA promulgated under CAA
section 112. When incorporated into CAA section 112(d) regulations for
specific source categories, these two provisions exempt sources from
the requirement to comply with the otherwise applicable CAA section
112(d) emissions standard during periods of SSM.
    We are proposing the elimination of the SSM exemption in this rule.
Consistent with Sierra Club v. EPA, the EPA is proposing standards in
this rule that apply at all times. We are also proposing several
revisions to Appendix A to subpart LL of part 63 (the General
Provisions Applicability table). For example, we are proposing to
eliminate the incorporation of the General Provisions' requirement that
the source develop an SSM plan. We also are proposing to eliminate or
revise certain recordkeeping and reporting requirements related to the
SSM exemption. The 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.

    In proposing the standards in this rule, the EPA has taken into
account startup and shutdown periods and, for the reasons explained
below, the EPA is proposing in some cases different standards for
startup periods.
    The 1997 MACT rule allowed for periods of up to six months for
startup of existing potlines that had been previously shutdown. These
long startup periods for potlines are recognized as part of the normal
operations during which emissions testing is not feasible. The current
MACT emission limits are not applicable during these startup periods.
Thus, we are proposing MACT standards for these periods in today's
action. Given that it is economically and technically infeasible to
measure emissions during these startup periods, we are proposing
detailed work practice standards that will minimize HAP emissions and
ensure proper operation of the processes and control equipment during
startup periods. The proposed work practices include bringing the
potline scrubbers and exhaust fans on line prior to energizing the
first cell being restarted, ensuring that the primary capture and
control system is operating at all times during startup, and keeping
pots covered during startup as much as practicable to include, but not
limited to, minimizing the removal of covers or panels of the pots on
which work is being performed. Moreover, facilities must inspect
potlines daily during startup and perform additional work practices,
including resealing pot crust as often and as soon as practicable,
reducing cell temperatures to as low as practicable, and adjusting pot
parameters to their optimum levels to include, but not limited to, the
following parameters: Alumina addition rate, exhaust air flow, cell
voltage, feeding level, anode current, and liquid and solid bath
levels.
    The 1997 MACT rule allowed for startup periods for new or
reconstructed anode bake furnaces and pitch storage tanks and for anode
bake furnaces that had been previously shutdown. Based on information
received from industry, we believe that these sources can comply with
their MACT standards during startup periods. Therefore, we are removing
the provisions for startup of anode bake furnaces and pitch storage
tanks. However, we have added startup practices for anode bake furnace
startup periods to help ensure that the standards will be met. These
startup practices will minimize HAP emissions and ensure proper
operation of the processes and control equipment during startup periods
(please refer to the discussion of the technology review in section
IV.D of this preamble).
    Shutdown emissions are not expected to be different from those
during normal operation; therefore, no separate standard or work
practice is warranted. We propose that the numerical MACT limits
described in previous sections of this preamble (established for normal
operations) will apply during shutdown periods. We also propose that
the MACT limits for all other affected units besides potlines (bake
furnaces, pitch tanks, and paste production plants) apply at all times,
including during startups and shutdowns.
    Information on periods of startup and shutdown received from the
industry indicate that emissions during startup (except for potlines)
and shutdown periods are no greater than emissions during normal
operations. Therefore, the continued operation of the existing control
devices and emission capture systems will, in conjunction with the
detailed proposed startup practices and work practices described above,
be consistent with maximum achievable control technology and will be
adequate, along with all the other standards described above, to ensure
that risks will be acceptable and the rule will provide an ample margin
of safety.
    Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. However, by
contrast, malfunction is defined as a ``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 * * *'' (40 CFR 63.2). The EPA has determined that CAA
section 112 does not require that emissions that occur during periods
of malfunction be factored into development of CAA section 112
standards. Under CAA section 112, emissions standards for new sources
must be no less stringent than the level ``achieved'' by the best
controlled similar source and for existing sources generally must be no
less stringent than the average emissions limitation ``achieved'' by
the best performing 12 percent of sources in the category. There is
nothing in CAA section 112 that directs the agency to consider
malfunctions in determining the level ``achieved'' by the best
performing or best controlled sources when setting emissions standards.
Moreover, while the EPA accounts for variability in setting emissions
standards consistent with the CAA section 112 case law, nothing in that
case law requires the agency to consider malfunctions as part of that
analysis. Section 112 of the CAA uses the concept of ``best
controlled'' and ``best performing'' unit in defining the level of
stringency that CAA section 112 performance standards must meet.
Applying the concept of ``best controlled'' or ``best performing'' to a
unit that is malfunctioning presents significant difficulties, as
malfunctions are sudden and unexpected events.
    Further, accounting for malfunctions would be difficult, if not
impossible, given the myriad different types of malfunctions that can
occur across all sources in the category and given the difficulties
associated with predicting or accounting for the frequency, degree, and
duration of various malfunctions that might occur. As such, the
performance of units that are malfunctioning is not ``reasonably''
foreseeable. See, e.g., Sierra Club v. EPA, 167 F.3d 658, 662 (DC Cir.
1999) (EPA typically has wide latitude in determining the extent of
data-gathering necessary to solve a problem. We generally defer to an
agency's decision to proceed on the basis of imperfect scientific
information, rather than to ``invest the resources to conduct the
perfect study.''). See also, Weyerhaeuser v. Costle, 590 F.2d 1011,
1058 (DC Cir. 1978) (``In the nature of things, no general limit,
individual permit, or even any upset provision can anticipate all upset
situations. After a certain point, the transgression of regulatory
limits caused by `uncontrollable acts of third parties,' such as
strikes, sabotage, operator intoxication or insanity, and a variety of
other eventualities, must be a matter for the administrative exercise
of case-by-case enforcement discretion, not for specification in
advance by regulation''). In addition, the goal of a best controlled or
best performing source is to operate in such a way as to avoid
malfunctions of the source, and accounting for malfunctions could lead
to standards that are significantly less stringent than levels that are
achieved by a well-performing non-malfunctioning source. The EPA's
approach to malfunctions is consistent with CAA section 112 and is a
reasonable interpretation of the statute.
    In the event that a source fails to comply with the applicable CAA
section 112(d) standards as a result of a malfunction event, the EPA
would determine an appropriate response based on, among other things,
the good faith efforts of the source to minimize emissions during
malfunction periods, including preventative and corrective actions, as
well as root cause analyses to ascertain and rectify excess emissions.
The EPA would also consider whether the source's failure to comply with
the CAA section 112(d)

standard was, in fact, ``sudden, infrequent, not reasonably
preventable'' and was not instead ``caused in part by poor maintenance
or careless operation'' 40 CFR 63.2 (definition of malfunction).
    Finally, the EPA recognizes that even equipment that is properly
designed and maintained can sometimes fail and that such failure can
sometimes cause an exceedance of the relevant emissions standard. (See,
e.g., State Implementation Plans: Policy Regarding Excessive Emissions
During Malfunctions, Startup, and Shutdown (Sept. 20, 1999); Policy on
Excess Emissions During Startup, Shutdown, Maintenance, and
Malfunctions (Feb. 15, 1983).). The EPA is therefore proposing to add
to the final rule an affirmative defense to civil penalties for
exceedances of emissions limits that are caused by malfunctions. See 40
CFR 63.842 (defining ``affirmative defense'' to mean, 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). We also are proposing other
regulatory provisions to specify the elements that are necessary to
establish this affirmative defense; the source must prove by a
preponderance of the evidence that it has met all of the elements set
forth in 40 CFR 63.855 (see also 40 CFR 22.24). The criteria ensure
that the affirmative defense is available only where the event that
causes an exceedance of the emissions limit meets the narrow definition
of malfunction in 40 CFR 63.2 (sudden, infrequent, not reasonably
preventable and not caused by poor maintenance and or careless
operation). For example, to successfully assert the affirmative
defense, the source must prove by a preponderance of the evidence that
excess emissions ``[w]ere caused by a sudden, infrequent, and
unavoidable failure of air pollution control and monitoring equipment,
process equipment, or a process to operate in a normal or usual manner
* * *.'' The criteria also are designed to ensure that steps are taken
to correct the malfunction, to minimize emissions in accordance with 40
CFR sections 63.843(f) and 63.844(f) to prevent future malfunctions.
For example, the source must prove by a preponderance of the evidence
that ``[r]epairs were made as expeditiously as possible when the
applicable emissions limitations were being exceeded * * *'' and that
``[a]ll possible steps were taken to minimize the impact of the excess
emissions on ambient air quality, the environment and human health * *
*.'' In any judicial or administrative proceeding, the Administrator
may challenge the assertion of the affirmative defense and, if the
respondent has not met its burden of proving all of the requirements in
the affirmative defense, appropriate penalties may be assessed in
accordance with CAA section 113 (see also 40 CFR 22.27).
    The EPA included an affirmative defense in the proposed rule in an
attempt to balance a tension, inherent in many types of air regulation,
to ensure adequate compliance while simultaneously recognizing that
despite the most diligent of efforts, emission limits may be exceeded
under circumstances beyond the control of the source. The EPA must
establish emission standards that ``limit the quantity, rate, or
concentration of emissions of air pollutants on a continuous basis.''
42 U.S.C. 7602(k) (defining ``emission limitation and emission
standard''). See generally Sierra Club v. EPA, 551 F.3d 1019, 1021 (DC
Cir. 2008). Thus, the EPA is required to ensure that section 112
emissions limitations are continuous. The affirmative defense for
malfunction events meets this requirement by ensuring that even where
there is a malfunction, the emission limitation is still enforceable
through injunctive relief. While ``continuous'' limitations, on the one
hand, are required, there is also case law indicating that in many
situations it is appropriate for EPA to account for the practical
realities of technology. For example, in Essex Chemical v. Ruckelshaus,
486 F.2d 427, 433 (DC Cir. 1973), the DC Circuit acknowledged that in
setting standards under CAA section 111 ``variant provisions'' such as
provisions allowing for upsets during startup, shutdown and equipment
malfunction ``appear necessary to preserve the reasonableness of the
standards as a whole and that the record does not support the `never to
be exceeded' standard currently in force.'' See also, Portland Cement
Association v. Ruckelshaus, 486 F.2d 375 (DC Cir. 1973). Though
intervening case law such as Sierra Club v. EPA and the CAA 1977
amendments undermine the relevance of these cases today, they support
the EPA's view that a system that incorporates some level of
flexibility is reasonable. The affirmative defense simply provides for
a defense to civil penalties for excess emissions that are proven to be
beyond the control of the source. By incorporating an affirmative
defense, the EPA has formalized its approach to upset events. In a
Clean Water Act setting, the Ninth Circuit required this type of
formalized approach when regulating ``upsets beyond the control of the
permit holder.'' Marathon Oil Co. v. EPA, 564 F.2d 1253, 1272-73 (9th
Cir. 1977). But see, Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1057-58
(DC Cir. 1978) (holding that an informal approach is adequate). The
affirmative defense provisions give the EPA the flexibility to both
ensure that its emission limitations are ``continuous'' as required by
42 U.S.C. 7602(k), and account for unplanned upsets and thus support
the reasonableness of the standard as a whole.
    Specifically, we are proposing the following rule changes:
     Add general duty requirements in 40 CFR sections 63.843
and 63.844 to replace General Provision requirements that reference
vacated SSM provisions.
     Add replacement language that eliminates the reference to
SSM exemptions applicable to performance tests in 40 CFR section
63.847(d).
     Add paragraphs in 40 CFR section 63.850(d) requiring the
reporting of malfunctions as part of the affirmative defense
provisions.
     Add paragraphs in 40 CFR section 63.850(e) requiring the
keeping of certain records during malfunctions as part of the
affirmative defense provisions.
     Revise Appendix A to subpart LL of part 63 to reflect
changes in the applicability of the General Provisions to this subpart
resulting from a court vacatur of certain SSM requirements in the
General Provisions.
2. Electronic Reporting
    The EPA must have performance test data to conduct effective
reviews of CAA sections 112 and 129 standards, as well as for many
other purposes including compliance determinations, emissions factor
development, and annual emissions rate determinations. In conducting
these required reviews, the EPA has found it ineffective and time
consuming, not only for us, but also for regulatory agencies and source
owners and operators, to locate, collect, and submit performance test
data because of varied locations for data storage and varied data
storage methods. In recent years, though, stack testing firms have
typically collected performance test data in electronic format, making
it possible to move to an electronic data submittal system that would
increase the ease and efficiency of data submittal and improve data
accessibility.
    Through this proposal the EPA is presenting a step to increase the
ease and efficiency of data submittal and

improve data accessibility. Specifically, the EPA is proposing that
owners and operators of Primary Aluminum Reduction Plant facilities
submit electronic copies of required performance test reports to the
EPA's WebFIRE database. The WebFIRE database was constructed to store
performance test data for use in developing emissions factors. A
description of the WebFIRE database is available at http://cfpub.epa.gov/oarweb/index.cfm?action=fire.main.
    As proposed above, data entry would be through an electronic
emissions test report structure called the Electronic Reporting Tool.
The ERT would be able to transmit the electronic report through the
EPA's Central Data Exchange network for storage in the WebFIRE database
making submittal of data very straightforward and easy. A description
of the ERT can be found at http://www.epa.gov/ttn/chief/ert/ert_tool.html.
    The proposal to submit performance test data electronically to the
EPA would apply only to those performance tests conducted using test
methods that will be supported by the ERT. The ERT contains a specific
electronic data entry form for most of the commonly used EPA reference
methods. A listing of the pollutants and test methods supported by the
ERT is available at http://www.epa.gov/ttn/chief/ert/ert_tool.html. We
believe that industry would benefit from this proposed approach to
electronic data submittal. Having these data, the EPA would be able to
develop improved emissions factors, make fewer information requests,
and promulgate better informed regulations.
    One major advantage of the proposed submittal of performance test
data through the ERT is a standardized method to compile and store much
of the documentation required to be reported by this rule. Another
advantage is that the ERT clearly states what testing information would
be required. Another important proposed benefit of submitting these
data to the EPA at the time the source test is conducted is that it
should substantially reduce the effort involved in data collection
activities in the future. When the EPA has performance test data in
hand, there will likely be fewer or less substantial data collection
requests in conjunction with prospective required residual risk
assessments or technology reviews. This would result in a reduced
burden on both affected facilities (in terms of reduced manpower to
respond to data collection requests) and the EPA (in terms of preparing
and distributing data collection requests and assessing the results).
    State, local, and Tribal agencies could also benefit from more
streamlined and accurate review of electronic data submitted to them.
The ERT would allow for an electronic review process rather than a
manual data assessment making review and evaluation of the source
provided data and calculations easier and more efficient. Finally,
another benefit of the proposed data submittal to WebFIRE
electronically is that these data would greatly improve the overall
quality of existing and new emissions factors by supplementing the pool
of emissions test data for establishing emissions factors and by
ensuring that the factors are more representative of current industry
operational procedures. A common complaint heard from industry and
regulators is that emissions factors are outdated or not representative
of a particular source category. With timely receipt and incorporation
of data from most performance tests, the EPA would be able to ensure
that emissions factors, when updated, represent the most current range
of operational practices. In summary, in addition to supporting
regulation development, control strategy development, and other air
pollution control activities, having an electronic database populated
with performance test data would save industry, state, local, Tribal
agencies, and the EPA significant time, money, and effort while also
improving the quality of emissions inventories and, as a result, air
quality regulations.
    Records must be maintained in a form suitable and readily available
for expeditious review, according to 63.10(b)(1). Electronic
recordkeeping and reporting is available for many records, and is the
form considered most suitable for expeditious review if available.
Electronic recordkeeping and reporting is encouraged in this proposal
and some records and reports are required to be kept in electronic
format.

F. Compliance Dates

    We are proposing that existing facilities must comply with the
proposed revised emissions limits for Soderberg potlines (which are
being proposed under CAA sections 112(f)(2) for all affected sources),
no later than 90 days after the date of publication of the final rule.
We are proposing that existing facilities must comply with all other
changes proposed in this action (other than affirmative defense
provisions and electronic reporting which are effective upon
promulgation of the final rule) no later than 3 years after the date of
publication of the final rule. All new or reconstructed facilities must
comply with all requirements in this rule upon startup.

V. Summary of Cost, Environmental, and Economic Impacts

A. What are the affected sources?

    The affected sources are new and existing potlines, new and
existing pitch storage tanks, new and existing anode bake furnaces
(except for one that is located at a facility that only produces anodes
for use off-site), and new and existing paste production plants.

B. What are the air quality impacts?

    The proposed rule will require the POM emissions from existing
uncontrolled pitch storage tanks to be reduced by a minimum of 95
percent. This is estimated to result in a reduction of 1.6 tons per
year (tpy) of POM. In addition, the proposed lower Soderberg potline
POM limits would reduce POM emissions from the two Soderberg
facilities, assuming production at plant capacity, by approximately 300
tpy, combined.

C. What are the cost impacts?

    Under the proposed amendments, 8 facilities would be required to
install or upgrade, and operate emissions control systems (such as
activated carbon adsorbers or condensers) to control emissions of HAP
from pitch storage tanks at total estimated cost of $167,832 per year,
or $20,979 per facility. In addition, 12 facilities will have to
conduct periodic performance tests for POM emissions from 45 prebake
potlines at an estimated total cost of $90,000 per year for the source
category, or $7,500 per year per facility. The total estimated cost of
the rule is $258,000 per year.

D. What are the economic impacts?

    We performed an economic impact analysis for the proposed
modifications in this rulemaking. That analysis estimates total
annualized costs of approximately $257,832 at 13 facilities and cost to
revenue of less than 0.02% for the Primary Aluminum Production source
category. For more information, please refer to the Draft Economic
Impact Analysis for this proposed rulemaking that is available in the
public docket for this proposed rulemaking.

E. What are the benefits?

    This proposed rule will achieve about 1.6 tons per year reductions
in POM emissions, which may result in a slight health benefit. The
proposed limits of 3.9 pounds of COS per ton of aluminum produced (lb
COS/ton Al) for existing facilities and 3.1 lb COS/ton Al for new

facilities will prevent increases in COS emissions and prevent
increases in SO2 emissions as a co-benefit. The proposed COS
standard will likely result in the use of lower sulfur content coke in
the anode production processes. This reduction in anode coke sulfur
content would result in decreases in emissions of both COS and sulfur
dioxide (SO2). We estimate that SO2 emissions
will decrease by 12 tons for each ton of COS reduction.

VI. Request for Comments

    We are soliciting comments on all aspects of this proposed action.
In addition to general comments on this proposed action, we are also
interested in any additional data that may help to reduce the
uncertainties inherent in the risk assessments and other analyses. We
are specifically interested in receiving corrections to the site-
specific emissions profiles 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. Section VII of this preamble provides more information on
submitting data.

VII. Submitting Data Corrections

    The site-specific emissions profiles used in the source category
risk 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 that 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.
Emissions Calculation Method Code   Code description of the method used
 for Revised Emissions.              to derive emissions. For example,
                                     CEM, material balance, stack test,
                                     etc.
Emissions Process Group...........  Enter the general type of emissions
                                     process associated with the
                                     specified emissions 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 Emissions Release Point     Enter revised Emissions Release
 Type.                               Point 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 Performance   Enter revised HAP Emissions
 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
                                     emissions 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 email
address, commenter phone number, and revision comments).
    3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations).
    4. Send the entire downloaded file with suggested revisions in
Microsoft[reg] Access format and all accompanying documentation to
Docket ID Number EPA-HQ-OAR-2011-0797 (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 RTR Web Page at: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory 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, the EPA submitted this action to the
Office of Management and Budget (OMB) for review under Executive Orders
12866 and 13563 (76 FR 3821, January 21, 2011) 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 the EPA has
been assigned the EPA ICR number 2447.01. The information collection
requirements are not enforceable until OMB approves them. The
information requirements are based on notification, recordkeeping, and
reporting requirements in the NESHAP General Provisions (40 CFR part
63, subpart A), which are mandatory for all operators subject to
national emissions standards. These recordkeeping and reporting
requirements are specifically authorized by CAA section 114 (42 U.S.C.
7414). All information submitted to the EPA pursuant to the
recordkeeping and reporting requirements for which a claim of
confidentiality is made is safeguarded according to agency policies set
forth in 40 CFR part 2, subpart B.
    We are proposing new paperwork requirements for the Primary
Aluminum Reduction Plant source category in the form of a one-time
requirement to prepare design specifications for existing pitch storage
tank controls, and submissions of test reports and calculations for
demonstration of compliance with prebake potline POM limits.
    For this proposed rule, the EPA is adding affirmative defense to
the estimate of burden in the ICR. To provide the public with an
estimate of the relative magnitude of the burden associated with an
assertion of the affirmative defense position adopted by a source, the
EPA has provided administrative adjustments to this ICR to show what
the notification, recordkeeping and reporting requirements associated
with the assertion of the affirmative defense might entail. The EPA's
estimate for the required notification, reports and records for any
individual incident, including the root cause analysis, totals $3,141
and is based on the time and effort required of a source to review
relevant data, interview plant employees, and document the events
surrounding a malfunction that has caused an exceedance of an emissions
limit. The estimate also includes time to produce and retain the record
and reports for submission to the EPA. The EPA provides this
illustrative estimate of this burden because these costs are only
incurred if there has been a violation and a source chooses to take
advantage of the affirmative defense.
    Given the variety of circumstances under which malfunctions could
occur, as well as differences among sources' operation and maintenance
practices, we cannot reliably predict the severity and frequency of
malfunction-related excess emissions events for a particular source. It
is important to note that the EPA has no basis currently for estimating
the number of malfunctions that would qualify for an affirmative
defense. Current historical records would be an inappropriate basis, as
source owners or operators previously operated their facilities in
recognition that they were exempt from the requirement to comply with
emissions standards during malfunctions. Of the number of excess
emissions events reported by source operators, only a small number
would be expected to result from a malfunction (based on the definition
above), and only a subset of excess emissions caused by malfunctions
would result in the source choosing to assert the affirmative defense.
Thus we believe the number of instances in which source operators might
be expected to avail themselves of the affirmative defense will be
extremely small.
    With respect to the Primary Aluminum Production source category,
the emissions controls are operational before the associated emission
source(s) commence operation and remain operational until after the
associated emission source(s) cease operation. Also, production
operations would not proceed or continue if there is a malfunction of a
control device and the time required to shut down production operations
(i.e., on the order of a day) is small compared to the averaging time
of the emission standards (i.e., monthly, quarterly and annual
averages). Thus, we believe it is unlikely that a control device
malfunction would cause an exceedance of any emission limit. Therefore,
sources within this source category are not expected to have any need
or use for the affirmative defense and we believe that there is no
burden to the industry for the affirmative defense provisions in the
proposed rule.
    We expect to gather information on such events in the future and
will revise this estimate as better information becomes available. We
estimate 15 regulated entities are currently subject to subpart LL and
will be subject to all proposed standards. The annual monitoring,
reporting, and recordkeeping burden for this collection (averaged over
the first 3 years after the effective date of the standards) for these
amendments to subpart LL is estimated

to be $148,000 per year. This includes 1,558 labor hours per year at a
total labor cost of $148,000 per year, and total non-labor capital and
operation and maintenance (O&M) costs of $500 per year. This estimate
includes performance tests, notifications, reporting, and recordkeeping
associated with the new requirements for existing pitch storage tanks
and new and existing potlines. The total burden for the Federal
government (averaged over the first 3 years after the effective date of
the standard) is estimated to be 120 hours per year at a total labor
cost of $11,400 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 the
EPA's regulations in 40 CFR are listed in 40 CFR part 9. When these
ICRs are approved by OMB, the agency will publish a technical amendment
to 40 CFR part 9 in the Federal Register to display the OMB control
numbers for the approved information collection requirements contained
in the final rules.
    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, the EPA has established a public docket
for this rule, which includes this ICR, under Docket ID number EPA-HQ-
OAR-2011-0797. Submit any comments related to the ICR to the EPA and
OMB. See the ADDRESSES section at the beginning of this notice for
where to submit comments to the 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
the EPA. Since OMB is required to make a decision concerning the ICR
between 30 and 60 days after December 6, 2011, a comment to OMB is best
assured of having its full effect if OMB receives it by January 5,
2012. 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 this proposed rule on
small entities, small entity is defined as: (1) A small business 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 that is independently owned and operated
and is not dominant in its field. For this source category, which has
the NAICS code 331312, the SBA small business size standard is 1,000
employees according to the SBA small business standards definitions.
There are no small entities subject to subpart LL.
    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. We
continue to be interested in the potential impacts of the proposed rule
on small entities and welcome comment 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 proposed
rule 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 the EPA
policy to promote communications between the EPA and State and local
governments, the EPA specifically solicits comment on this proposed
rule from State and local officials.

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

    This proposed rule does not have Tribal implications, as specified
in Executive Order 13175 (65 FR 67249, November 9, 2000). None of the
provisions of this proposed rule will result in increased emissions of
any hazardous air pollutant from any facility. The more stringent
limitations of POM emissions from horizontal stud Soderberg potlines
may result in decreased risk to Indian Tribal populations. Thus,
Executive Order 13175 does not apply to this action.
    The 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. Moreover, the agency does not believe
the environmental health risks or safety risks addressed by this action
present a disproportionate risk to children. Nevertheless, the public
is invited to submit comments or identify studies and data that assess
effects of early life exposure to HAP from Primary Aluminum sources.
The EPA will typically accord greater weight to studies and data that
have been peer reviewed.

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 and therefore no additional
costs 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 (15 U.S.C. 272 note),
directs the EPA to use voluntary consensus standards (VCS) in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. VCS are technical standards
(e.g., materials specifications, test methods, sampling procedures, and
business practices) that are developed or adopted by voluntary
consensus standards bodies. NTTAA directs the EPA to provide Congress,
through OMB, explanations when the agency decides not to use available
and applicable VCS.
    This proposed rulemaking involves technical standards. The EPA
proposes to use ASTM D3177-02 (2007) Standard Test Methods for Total
Sulfur in the Analysis Sample of Coal and Coke. This is a voluntary
consensus method. This method can be obtained from the American Society
for Testing and Materials, 100 Bar Harbor Drive, West Conshohocken,
Pennsylvania 19428 (telephone number<PHONE_NUMBER>). This method was
proposed because it is commonly used by primary aluminum reduction
facilities to demonstrate compliance with sulfur dioxide emission
limitations imposed in their current Title V permits. The EPA welcomes
comments on this aspect of this proposed rulemaking and, specifically,
invites the public to identify potentially-applicable voluntary
consensus standards and to explain why such standards should be used in
this regulation.

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.
    For the primary aluminum source category, EPA has determined that
the current health risks posed to anyone by actual emissions from this
source category are within the acceptable range, and that the proposed
rulemaking will not appreciably reduce these risks further. As a
result, this proposed rule will not have disproportionately high and
adverse human health or environmental effects on minority or low-income
populations.
    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 this source category is
located. The methods used to conduct demographic analyses for this rule
are described in the document Draft Residual Risk Assessment for the
Primary Aluminum Reduction Plant Source Category which may be found in
the docket for this rulemaking. The development of demographic analyses
to inform the consideration of environmental justice issues in the EPA
rulemakings is an evolving science. The EPA offers the demographic
analyses in today's proposed 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.
    In the demographics analysis, we focused on populations within 50
km of the facilities in this source category with emissions sources
subject to the MACT standard. More specifically, for these populations
we evaluated exposures to HAP that could result in cancer risks of 1 in
one million or greater. 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 the document Draft Residual Risk Assessment
for the Primary Aluminum Reduction Plant Source Category in the docket
for this proposed rulemaking.

List of Subjects in 40 CFR Part 63

    Environmental protection, Air pollution control, Hazardous
substances, Incorporation by reference, Reporting and recordkeeping
requirements.

    Dated: November 4, 2011.
Lisa P. Jackson,
Administrator.

    For the reasons stated in the preamble, part 63 of title 40,
chapter I, of the Code of Federal Regulations is proposed to be amended
as follows:

PART 63--[AMENDED]

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

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

Subpart LL--[AMENDED]

    2. Section 63.840 is amended by revising paragraph (a) to read as
follows:

Sec.  63.840  Applicability.

    (a) Except as provided in paragraph (b) of this section, the
requirements of this subpart apply to the owner or operator of each new
or existing pitch storage tank, potline, paste production plant and
anode bake furnace associated with primary aluminum production and
located at a major source as defined in Sec.  63.2.
* * * * *
    3. Section 63.841 is amended by adding paragraph (a)(3) to read as
follows:

Sec.  63.841  Incorporation by reference.

    (a) * * *
    (3) ASTM D3177-02 (2007) Standard Test Methods for Total Sulfur in
the Analysis Sample of Coal and Coke.
* * * * *
    4. Section 63.842 is amended to read as follows:
    a. Removing the definition for ``Vertical stud Soderberg one
(VSS1)'' and
    b. Adding, in alphabetical order, definitions for ``Affirmative
defense'' and ``Startup of an anode bake furnace''

Sec.  63.842  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.
* * * * *
    Startup of an anode bake furnace means the process of initiating
heating to the anode baking furnace where all sections of the furnace
have previously been at ambient temperature. The startup or re-start of
the furnace begins when the heating begins. The startup or

re-start concludes at the start of the second anode bake cycle.
* * * * *
    5. Section 63.843 is amended to read as follows:
    a. Revising paragraph (a)(1)introductory text;
    b. Removing and reserving paragraph (a)(1)(v);
    c. Revising paragraph (a)(2)introductory text, and (a)(2)(i);
    d. Removing and reserving paragraph (a)(2)(ii);
    e. Revising paragraph (a)(2)(iii); and
    f. Adding paragraphs (a)(2)(iv) through (a)(2)(vii), (d), (e), and
(f)

Sec.  63.843  Emission limits for existing sources.

    (a) * * *
    (1) Emissions of TF must not exceed:
* * * * *
    (v) [Reserved]
* * * * *
    (2) Emissions of POM must not exceed:
    (i) 1.5 kg/Mg (3.0 lb/ton) of aluminum produced for each HSS
potline;
    (ii) [Reserved;]
    (iii) 1.9 kg/Mg (3.8 lb/ton) of aluminum produced for each VSS2
potline;
    (iv) 0.31 kg/Mg (0.62 lb/ton) of aluminum produced for each
existing CWPB1 prebake potline;
    (v) 0.65 kg/Mg (1.3 lb/ton) of aluminum produced for each existing
CWPB2 prebake potline;
    (vi) 0.63 kg/Mg (1.26 lb/ton) of aluminum produced for each
existing CWPB3 prebake potline;
    (vii) 0.33 kg/Mg (0.65 lb/ton) of aluminum produced for each
existing SWPB prebake potline;
* * * * *
    (d) Pitch storage tanks. Each pitch storage tank shall be equipped
with an emission control system designed and operated to reduce inlet
emissions of POM by 95 percent or greater.
    (e) COS limit. Emissions of COS must not exceed 3.9 lb/ton of
aluminum produced.
    (f) 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 63.844 is amended to read as follows:
    a. Adding paragraph (a)(3);
    b. Adding paragraph (e); and
    c. Adding paragraph (f)

Sec.  63.844  Emission limits for new or reconstructed sources.

    (a) * * *
    (3) POM limit. Emissions of POM from prebake potlines must not
exceed 0.31 kg/Mg (0.62 lb/ton) of aluminum produced.
* * * * *
    (e) COS limit. Emissions of COS must not exceed 3.1 lb/ton of
aluminum produced.
    (f) 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.
    7. Section 63.846 is amended to read as follows:
    a. Revising paragraph (b);
    b. Revising paragraph (d)(2)(iv);
    c. Revising paragraphs (d)(4)(ii) and (iii);
    d. Removing and reserving paragraph (d)(4)(iv); and
    e. Adding paragraphs (e) and (f)

Sec.  63.846  Emission averaging.

* * * * *
    (b) Soderberg Potlines. The owner or operator may average TF
emissions from potlines and demonstrate compliance with the limits in
Table 1 of this subpart using the procedures in paragraphs (b)(1) and
(b)(2) of this section. The owner or operator also may average POM
emissions from potlines and demonstrate compliance with the limits in
Table 2 of this subpart using the procedures in paragraphs (b)(1) and
(b)(3) of this section.
* * * * *
    (d) * * *
    (2) * * *
    (iv) The test plan for the measurement of TF or POM emissions in
accordance with the requirements in Sec. Sec.  63.847(b) and (k);
* * * * *
    (4) * * *
    (ii) The inclusion of any emission source other than an existing
potline or existing anode bake furnace subject to the same operating
permit; or
    (iii) The inclusion of any potline or anode bake furnace while it
is shut down, in the emission calculations.
    (iv) [Reserved]
* * * * *
    (e) TF emissions from Prebake Potlines. The owner or operator may
average TF emissions from potlines and demonstrate compliance with the
limits in Table 1 of this subpart using the procedures in paragraphs
(e)(1) and (e)(2) of this section.
    (1) Monthly average emissions of TF must not exceed the applicable
emission limit in Table 1 of this subpart. The emission rate must be
calculated based on the total emissions from all potlines over the
period divided by the quantity of aluminum produced during the period,
from all potlines comprising the averaging group.
    (2) To determine compliance with the applicable emission limit in
Table 1 of this subpart for TF emissions, the owner or operator must
determine the monthly average emissions (in lb/ton) from each potline
from at least three runs per potline each month for TF secondary
emissions using the procedures and methods in Sec. Sec.  63.847 and
63.849. The owner or operator must combine the results of secondary TF
monthly average emissions with the TF results for the primary control
system and divide total emissions by total aluminum production.
    (f) POM Emissions from Prebake Potlines. The owner or operator also
may average POM emissions from potlines and demonstrate compliance with
the limits in Table 2 of this subpart using the procedures in
paragraphs (f)(1) and (f)(2) of this section.
    (1) Average emissions of POM for each compliance demonstration
period, must not exceed the applicable emission limit in Table 2 of
this subpart. The emission rate must be calculated based on the total
emissions from all potlines divided by the quantity of aluminum
produced during the period, from all potlines comprising the averaging
group.
    (2) To determine compliance with the applicable emission limit in
Table 2 of this subpart for POM emissions, the owner or operator must
determine the emissions (in lb/ton) from each potline using the
procedures and methods in Sec. Sec.  63.847 and 63.849. The owner or
operator must combine the results of measured or calculated secondary
POM emissions with the POM emissions from the primary control system
and divide

total emissions by total aluminum production.
    8. Section 63.847 is amended to read as follows:
    a. Revising paragraph (a)
    b. Removing and reserving paragraph (a)(3);
    c. Revising paragraph (b) introductory text;
    d. Removing and reserving paragraph (b)(6);
    e. Revising paragraphs (c)(1); (c)(2); and (c)(3);
    f. Removing paragraphs (c)(2)(i) through (iii);
    g. Revising paragraph (c)(3);
    h. Revising paragraphs (d) introductory text and (d)(2);
    i. Adding paragraph (d)(5);
    j. Revising paragraph (e)(2);
    k. Adding paragraph (e)(8);
    l. Revising paragraph (g) introductory text;
    m. Adding and reserving paragraph (i); and
    n. Adding paragraphs (j), (k), (l), and (m).
    The revisions and additions read as follows:

Sec.  63.847  Compliance Provisions.

    (a) Compliance dates. The owner operator of a primary aluminum
reduction plant must comply with the requirements of this subpart by
the applicable compliance date in paragraph (a)(1), (a)(2) or (a)(3) of
this section:
    (1) Except as noted in paragraph (a)(2) of this section, the
compliance date for an owner or operator of an existing plant or source
subject to the provisions of this subpart is October 7, 1999.
    (2) The compliance dates for existing plants and sources are:
    (i) [Date 90 days after date of publication of final rule] for
Soderberg potlines subject to emission limits in Sec. Sec.
63.843(a)(2)(i) and (iii) which became effective [Date of publication
of final rule].
    (ii) [Date 3 years after date of publication of final rule] for
prebake potlines subject to emission limits in Sec. Sec.
63.843(a)(2)(iv) through (vii) and Sec.  63.848(n) which became
effective [Date of publication of final rule].
    (iii) [Date 3 years after date of publication of final rule] for
potlines subject to the work practice standards in Sec.  63.854 which
became effective [insert date of publication of final rule].
    (iv) [Date 3 years after date of publication of final rule] for
anode bake furnaces subject to the startup practices in Sec.  63.847(m)
which became effective [insert date of publication of final rule].
    (v) [Date 3 years after date of publication of final rule] for
compliance with the pitch storage tank POM limit provisions of Sec.
63.843(d) and the COS emission limit provisions of Sec. Sec.  63.843(e)
and 63.844(e).
    (vi) [Date of publication of final rule] for the malfunction
provisions of Sec. Sec.  63.850(d)(2) and (e)(4)(xvi) and (xvii), the
affirmative defense provisions of Sec.  63.855, and the electronic
reporting provisions of Sec. Sec.  63.850(c) and (f).
    (3) [Reserved]
* * * * *
    (b) Test plan for TF from all anode bake furnaces and potlines and
POM from Soderberg potlines. The owner or operator shall prepare a
site-specific test plan prior to the initial performance test according
to the requirements of Sec.  63.7(c) of this part. The test plan must
include procedures for conducting the initial performance test and for
subsequent performance tests required in Sec.  63.848 for emission
monitoring. In addition to the information required by Sec.  63.7, the
test plan shall include:
* * * * *
    (6) [Reserved]
* * * * *
    (c) * * *
    (1) During the first month following the compliance date for an
existing potline (or potroom group), anode bake furnace or pitch
storage tank;
    (2) By the 180th day following startup for a potline or potroom
group for which the owner or operator elects to conduct an initial
performance test. The 180-day period starts when the first pot in a
potline or potroom group is energized.
    (3) By the 180th day following startup for a potline or potroom
group that was shut down at the time compliance would have otherwise
been required and is subsequently restarted. The 180-day period starts
when the first pot in a potline or potroom group is energized.
    (d) Performance test requirements. The initial performance test and
all subsequent performance tests must be conducted in accordance with
the requirements of the general provisions in subpart A of this part,
the approved test plan, and the procedures in this section. Performance
tests must 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 must make available to the Administrator such records
as may be necessary to determine the conditions of performance tests.
* * * * *
    (2) POM emissions from Soderberg potlines. For each Soderberg (HSS
and VSS2) potline, the owner or operator must measure and record the
emission rate of POM exiting the primary emission control system and
the rate of secondary emissions exiting through each roof monitor, or
for a plant with roof scrubbers, exiting through the scrubbers. Using
the equation in paragraph (e)(2) of this section, the owner or operator
must compute and record the average of at least three runs each quarter
(one run per month) for secondary emissions and at least three runs
each year for the primary control system to determine compliance with
the applicable emission limit. Compliance is demonstrated when the
emission rate of POM is equal to or less than the applicable emission
limit in Sec. Sec.  63.843, 63.844 or 63.846.
* * * * *
    (5) POM emissions from prebake potlines. For each prebake potline,
the owner or operator shall measure and record the emission rate of POM
exiting the primary emission control system. The owner or operator
shall compute and record the average of at least three runs every five
years. For each prebake potline for which the owner or operator chooses
to demonstrate compliance using the provisions of Sec.  63.847(e)(2),
the owner or operator shall measure and record the emission rate of
secondary emissions exiting through each roof monitor, or for a plant
with roof scrubbers, exiting through the scrubbers. The owner or
operator shall compute and record the average of at least three runs
every five years for secondary emissions. The owner or operator shall
calculate POM emissions in accordance with Sec. Sec.  63.847(e)(2) or
(8). Compliance is demonstrated when the emission rate of POM is equal
to or less than the applicable emission limit in Sec. Sec.  63.843,
63.844 or 63.846.
    (e) * * *
    (2) Compute the emission rate of POM from each Soderberg potline,
and from those prebake potlines for which the owner or operator chooses
to measure secondary emissions, using Equation 1,

Where:

Ep = emission rate of POM from the potline, kg/mg (lb/
ton); and
Cs = concentration of POM, mg/dscm (mg/dscf). POM
emission data collected during the installation and startup of a
cathode must not be included in Cs.
* * * * *
    (8) Compute the rate of POM from each prebake potline for which the
owner or operator does not choose to determine the measure the
secondary emissions using Equation 3:

[GRAPHIC] [TIFF OMITTED] TP06DE11.006

Where:

Epp = emission rate of POM from a potline, kg/Mg (lb/
ton);
Cpp1 = concentration of POM from the primary control
system, mg/dscm (mg/dscf);
Q1 = volumetric flow rate of effluent gas from the
primary control system dscm/hr (dscf/hr);
CpF2 = concentration of TF from the secondary control
system or roof monitor, mg/dscm (mg/dscf);
CpF1 = concentration of TF from the primary control
system, mg/dscm (mg/dscf); and
Q2 = volumetric flow rate of effluent gas from the
secondary control system or roof monitor, dscm/hr (dscf/hr).
* * * * *
    (g) Pitch storage tanks. The owner or operator must demonstrate
initial compliance with the standard for pitch storage tanks in
Sec. Sec.  63.843(d) and 63.844(d) by preparing a design evaluation or
by conducting a performance test. The owner or operator shall submit
for approval by the regulatory authority the information specified in
paragraph (g)(1) of this section, along with the information specified
in paragraph (g)(2) of this section where a design evaluation is
performed or the information specified in paragraph (g)(3) of this
section where a performance test is conducted.
* * * * *
    (i) [Reserved]
    (j) COS Emissions. The owner operator of each plant must calculate
the facility wide emission rate of COS for each calendar month of
operation using the following equation:
[GRAPHIC] [TIFF OMITTED] TP06DE11.007

Where:

ECOS = the facility wide emission rate of COS during the
calendar month in pounds per ton of aluminum produced;
K = factor accounting for molecular weights and conversion of sulfur
to carbonyl sulfide = 234;
Y = the tons of anode used at the facility during the calendar
month;
Z = the tons of aluminum produced at the facility during the
calendar month; and
%S = the weighted average sulfur content of the anode coke utilized
in the production of aluminum during the calendar month (e.g., if
the weighted average sulfur content of the anode coke utilized
during the calendar month was 2.5%, then %S = 0.025).

    Compliance is demonstrated if the calculated value of
ECOS is less than the applicable standard for COS emissions
in Sec. Sec.  63.843(e) and 63.844(e).
    (k) Test plan POM from prebake potlines. The owner or operator must
prepare a site-specific test plan prior to the initial performance test
according to the requirements of Sec.  63.7(c) of this part. The test
plan must include procedures for conducting the initial performance
test and for subsequent performance tests required in Sec.  63.848 for
emission monitoring. In addition to the information required by Sec.
63.7 the test plan shall include:
    (1) Procedures to ensure a minimum of three runs are performed for
the primary control system for each source;
    (2) For a source with a single control device exhausted through
multiple stacks, procedures to ensure that at least three runs are
performed by a representative sample of the stacks satisfactory to the
applicable regulatory authority;
    (3) For multiple control devices on a single source, procedures to
ensure that at least one run is performed for each control device by a
representative sample of the stacks satisfactory to the applicable
regulatory authority;
    (4) For plants with roof scrubbers, procedures for rotating
sampling among the scrubbers or other procedures to obtain
representative samples as approved by the applicable regulatory
authority.
    (l) Potlines. The owner or operator shall develop a written startup
plan as described in Sec.  63.854 that contains specific procedures to
be followed during startup periods of potline(s). Compliance with the
applicable standards in Sec.  63.854 will be demonstrated through site
inspection(s) and review of site records by the applicable regulatory
authority.
    (m) Anode bake furnaces. If you own or operate a new or existing
primary aluminum reduction affected source, you must develop a written
startup plan as described in paragraphs (m)(1) through (4) of this
section. Compliance with the startup plan will be demonstrated through
site inspection(s) and review of site records by the applicable
regulatory authority. The written startup plan must contain specific
procedures to be followed during startup periods of anode bake
furnaces, including the following:
    (1) A requirement to develop an anode bake furnace startup schedule
prior to startup of the first anode bake furnace.
    (2) Records of time, date, duration and any nonroutine actions
taken during startup of the furnaces.
    (3) A requirement that the associated emission control system
should be operating within normal parametric limits prior to startup of
the first anode bake furnace.
    (4) A requirement to shut down the anode bake furnaces immediately
if the associated emission control system is off line at any time
during startup.
    9. Section 63.848 is amended by revising paragraph (b) and adding
paragraph (n) to read as follows:

Sec.  63.848  Emission monitoring requirements.

* * * * *
    (b) POM emissions from Soderberg potlines. Using the procedures in
Sec.  63.847 and in the approved test plan, the owner or operator shall
monitor emissions of POM from each Soderberg (HSS and VSS2) potline
every three months. The owner or operator shall compute and record the
quarterly (3-month) average from at least one run per month for
secondary emissions and the previous 12-month average of all runs for
the primary control systems to determine compliance with the applicable
emission limit. The owner or operator must include all valid runs in
the quarterly (3-month) average. The duration of each run for secondary
emissions must represent a complete operating cycle. The primary
control system must be sampled over an 8-hour period, unless site-
specific factors dictate an alternative sampling time subject to the
approval of the regulatory authority.
* * * * *
    (n) POM emissions from prebake potlines. Using the procedures in
Sec.  63.847 and in the approved test plan, the owner or operator must
monitor emissions of POM from each prebake potline every five years.
The owner or operator must compute and record the sum of the average
primary and secondary emissions using the procedures of Sec. Sec.
63.847(e)(2) or (e)(8).
    10. Section 63.849 is amended by adding paragraph (f) to read as
follows:

Sec.  63.849  Test methods and procedures.

* * * * *
    (f) The owner or operator must use ASTM Method D3177--02 (2007) for
determination of the sulfur content in anode coke shipments to
determine

compliance with the applicable facility wide emission limit for COS
emissions.
    11. Section 63.850 is amended to read as follows:
    a. Revising paragraphs (c) and (d);
    b. Removing and reserving paragraph (e)(4)(iii); and
    c. Adding paragraphs (e)(4)(xvi), (e)(4)(xvii) and (f).
    The revisions and additions read as follows:

Sec.  63.850  Notification, reporting and recordkeeping requirements.

* * * * *
    (c) As of January 1, 2012, and within 60 days after the date of
completing each performance test, as defined in Sec.  63.2, and as
required in this subpart, the owner or operator must submit performance
test data, except opacity data, electronically to the EPA's Central
Data Exchange by using the ERT (see http://www.epa.gov/ttn/chief/ert/erttool.html/) or other compatible electronic spreadsheet. Only data
collected using test methods compatible with ERT are subject to this
requirement to be submitted electronically into the EPA's WebFIRE
database.
    (d) Reporting. In addition to the information required under Sec.
63.10 of the General Provisions, the owner or operator must provide
semi-annual reports containing the information specified in paragraphs
(d)(1) through (d)(2) of this section to the Administrator or
designated authority.
    (1) Excess emissions report. As required by Sec.  63.10(e)(3), the
owner or operator must submit a report (or a summary report) if
measured emissions are in excess of the applicable standard. The report
must contain the information specified in Sec.  63.10(e)(3)(v) and be
submitted semiannually unless quarterly reports are required as a
result of excess emissions.
    (2) If there was a malfunction during the reporting period, the
owner or operator must submit a report that includes the number,
duration, and a brief description for each type of malfunction which
occurred during the reporting period and which caused or may have
caused any applicable emission limitation to be exceeded. The report
must also include a description of actions taken by an owner or
operator during a malfunction of an affected source to minimize
emissions in accordance with Sec. Sec.  63.843(f) and 63.844(f),
including actions taken to correct a malfunction.
    (e) * * *
    (4) * * *
    (iii) [Reserved]
* * * * *
    (xvi) Records of the occurrence and duration of each malfunction of
operation (i.e., process equipment) or the air pollution control
equipment and monitoring equipment.
    (xvii) Records of actions taken during periods of malfunction to
minimize emissions in accordance with Sec. Sec.  63.843 and 63.844,
including corrective actions to restore malfunctioning process and air
pollution control and monitoring equipment to its normal or usual
manner of operation.
    (f) All reports required by this subpart not subject to the
requirements in paragraph (b) of this section must be sent to the
Administrator at the appropriate address listed in Sec.  63.13. If
acceptable to both the Administrator and the owner or operator of a
source, these reports may be submitted on electronic media. The
Administrator retains the right to require submittal of reports subject
to paragraph (b) of this section in paper format.
    12. Section 63.854 is added to read as follows:

Sec.  63.854  Work Practice Standards for Periods of Startup.

    (a) Startup of potlines. If you own or operate a new or existing
primary aluminum reduction affected source, you must comply with the
requirements of paragraphs (a)(1) through (7) of this section during
startup for each affected potline.
    (1) Develop a potline startup schedule before starting up the
potline.
    (2) Keep records of number of pots started per day.
    (3) Bring the potline scrubbers and exhaust fans on line prior to
energizing the first cell being restarted.
    (4) Ensure that the primary capture and control system is operating
at all times during startup.
    (5) Keep pots covered during startup as much as practicable to
include but not limited to minimizing the removal of covers or panels
of the pots on which work is being performed.
    (6) Inspect potlines daily during startup and perform the following
work practices as specified in paragraphs (a)(6)(i) through (iv) of
this section.
    (i) Identify unstable pots as soon as practicable but in no case
more than 12 hours from the time the pot became unstable;
    (ii) Reduce cell temperatures to as low as practicable, but no
higher than the maximum temperature specified in the operating plan
described in paragraph (a)(7) of this section;
    (iii) Reseal pot crusts that have been broken as often and as soon
as practicable but in no case more than 24 hours from the time the
crust was broken; and
    (iv) Adjust pot parameters to their optimum levels, as specified in
the operating plan described in paragraph (a)(7) of this section,
including, but not limited to, the following parameters: Alumina
addition rate, exhaust air flow, cell voltage, feeding level, anode
current and liquid and solid bath levels.
    (7) Prepare a written operating plan to minimize emissions during
startup to include, but not limited to, the requirements in (a)(1)
through (6) of this section.
    13. Section 63.855 is added to read as follows:

Sec.  63.855  Affirmative defense for exceedance of emission limit
during malfunction.

    In response to an action to enforce the standards set forth in this
subpart, you may assert an affirmative defense to a claim for civil
penalties for exceedances of such standards that are caused by
malfunction, as defined at Sec.  63.2. Appropriate penalties may be
assessed, however, if you fail to meet your burden of proving all of
the requirements in the affirmative defense. The affirmative defense
shall not be available for claims for injunctive relief.
    (a) To establish the affirmative defense in any action to enforce
such a limit, you must timely meet the notification requirements in
Sec.  63.850, and must prove by a preponderance of evidence that:
    (1) The excess emissions:
    (i) Were caused by a sudden, infrequent, and unavoidable failure of
air pollution control and monitoring equipment, process equipment, or a
process to operate in a normal or usual manner; and
    (ii) Could not have been prevented through careful planning, proper
design or better operation and maintenance practices; and
    (iii) Did not stem from any activity or event that could have been
foreseen and avoided, or planned for.
    (iv) Were not part of a recurring pattern indicative of inadequate
design, operation, or maintenance; and
    (2) Repairs were made as expeditiously as possible when the
applicable emissions limitations were being exceeded. Off-shift and
overtime labor were used, to the extent practicable to make these
repairs; and
    (3) The frequency, amount and duration of the excess emissions
(including any bypass) were minimized to the maximum extent practicable
during periods of such emissions; and
    (4) If the excess emissions resulted from a bypass of control
equipment or a process, then the bypass was unavoidable to prevent loss
of life,

personal injury, or severe property damage; and
    (5) All possible steps were taken to minimize the impact of the
excess emissions on ambient air quality, the environment and human
health; and
    (6) All emissions monitoring and control systems were kept in
operation if at all possible, consistent with safety and good air
pollution control practices; and
    (7) All of the actions in response to the excess emissions were
documented by properly signed, contemporaneous operating logs; and
    (8) At all times, the affected source was operated in a manner
consistent with good practices for minimizing emissions; and
    (9) A written root cause analysis has been prepared, the purpose of
which is to determine, correct, and eliminate the primary causes of the
malfunction and the excess emissions resulting from the malfunction
event at issue. The analysis shall also specify, using best monitoring
methods and engineering judgment, the amount of excess emissions that
were the result of the malfunction.
    (b) Notification. The owner or operator of the affected source
experiencing an exceedance of its emissions limit(s) during a
malfunction, shall notify the Administrator by telephone or facsimile
transmission as soon as possible, but no later than two business days
after the initial occurrence of the malfunction, if it wishes to avail
itself of an affirmative defense to civil penalties for that
malfunction. The owner or operator seeking to assert an affirmative
defense, shall also submit a written report to the Administrator within
45 days of the initial occurrence of the exceedance of the standards in
this subpart to demonstrate, with all necessary supporting
documentation, that it has met the requirements set forth in paragraph
(e) of this section. The owner or operator may seek an extension of
this deadline for up to 30 additional days by submitting a written
request to the Administrator before the expiration of the 45 day
period. Until a request for an extension has been approved by the
Administrator, the owner or operator is subject to the requirement to
submit such report within 45 days of the initial occurrence of the
exceedance.
    14. Table 1 to Subpart LL of Part 63 is revised to read as follows:

                   Table 1 to Subpart LL of Part 63--Potline TF Limits for Emission Averaging
----------------------------------------------------------------------------------------------------------------
                                    Monthly TF limit (1b/ton) (for given number of potlines)
     Type     --------------------------------------------------------------------------------------------------
                  2 lines        3 lines       4 lines       5 lines       6 lines       7 lines       8 lines
----------------------------------------------------------------------------------------------------------------
    CWPB1              1.7            1.6           1.5           1.5           1.4           1.4           1.4
    CWPB2              2.9            2.8           2.7           2.7           2.6           2.6           2.6
    CWPB3              2.3            2.2           2.2           2.1           2.1           2.1           2.1
     VSS2              2.6            2.5           2.5           2.4           2.4           2.4           2.4
      HSS              2.5            2.4           2.4           2.3           2.3           2.3           2.3
     SWPB              1.4            1.3           1.3           1.2           1.2           1.2           1.2
----------------------------------------------------------------------------------------------------------------

    15. Table 2 to Subpart LL of Part 63 is revised to read as follows:

                   Table 2 to Subpart LL of Part 63--Potline POM Limits for Emission Averaging
----------------------------------------------------------------------------------------------------------------
                                       POM limit (lb/ton) (for given number of potlines)
     Type     --------------------------------------------------------------------------------------------------
                  2 lines        3 lines       4 lines       5 lines       6 lines       7 lines       8 lines
----------------------------------------------------------------------------------------------------------------
      HSS              3.5            3.2           3.1           3.0           3.0           2.9           2.8
     VSS2              3.5            3.3           3.2           3.1           3.0           2.9           2.9
    CWPB1              0.63           0.56          0.52          0.52          0.48          0.48          0.48
    CWBP2              1.4            1.35          1.31          1.31          1.26          1.26          1.26
    CWBP3              1.33           1.28          1.28          1.26          1.26          1.26          1.26
     SWPB              0.63           0.56          0.52          0.52          0.48          0.48          0.48
----------------------------------------------------------------------------------------------------------------

    16. Appendix A to Subpart LL of Part 63 is revised to read as
follows:

Appendix A to Subpart LL of Part 63--Applicability of General
Provisions (40 CFR Part 63, Subpart A)

------------------------------------------------------------------------
                               Applies to  subpart
 Reference Section(s) * * *            LL                  Comment
------------------------------------------------------------------------
63.1........................  Yes.                  ....................
63.2........................  Yes.                  ....................
63.3........................  Yes.                  ....................
63.4........................  Yes.                  ....................
63.5........................  Yes.                  ....................
63.6(a), (b), (c)...........  Yes.                  ....................
63.6(d).....................  No..................  Section reserved.
63.6(e)(1)(i)...............  No..................  See Sec.  Sec.
                                                     63.843(f) and
                                                     63.844(f) for
                                                     general duty
                                                     requirement.
63.6(e)(1)(ii)..............  No.                   ....................
63.6(e)(1)(iii).............  Yes.                  ....................

63.6(e)(2)..................  No..................  Section reserved.
63.6(e)(3)..................  No.                   ....................
63.6(f)(1)..................  No.                   ....................
63.6(g).....................  Yes.                  ....................
63.6(h).....................  No..................  No opacity limits in
                                                     rule.
63.6(i).....................  Yes.                  ....................
63.6(j).....................  Yes.                  ....................
63.7(a) through (d).........  Yes.                  ....................
63.7(e)(1)..................  No..................  See Sec.
                                                     63.847(d).
63.7(e)(2) through (e)(4)...  Yes.                  ....................
63.7(f), (g), (h)...........  Yes.                  ....................
63.8(a) and (b).............  Yes.                  ....................
63.8(c)(1)(i)...............  No..................  See Sec.  Sec.
                                                     63.843(f) and
                                                     63.844(f) for
                                                     general duty
                                                     requirement.
63.8(c)(1)(ii)..............  Yes.                  ....................
63.8(c)(1)(iii).............  No.                   ....................
63.8(c)(2) through (d)(2)...  Yes.                  ....................
63.8(d)(3)..................  Yes, except for last  ....................
                               sentence.
63.8(e) through (g).........  Yes.                  ....................
63.9(a), (b), (c), (e), (g),  Yes.                  ....................
 (h)(1) through (3), (h)(5)
 and (6), (i) and (j).
63.9(f).....................  No.                   ....................
63.9(h)(4)..................  No..................  Section reserved.
63.10(a)....................  Yes.                  ....................
63.10(b)(1).................  Yes.                  ....................
63.10(b)(2)(i)..............  No.                   ....................
63.10(b)(2)(ii).............  No..................  See Sec.  Sec.
                                                     63.850(e)(4)(xvi)
                                                     and (xvii) for
                                                     recordkeeping of
                                                     occurrence and
                                                     duration of
                                                     malfunctions and
                                                     recordkeeping of
                                                     actions taken
                                                     during malfunction.
63.10(b)(2)(iii)............  Yes.                  ....................
63.10(b)(2)(iv) and           No.                   ....................
 (b)(2)(v).
63.10(b)(2)(vi) through       Yes.                  ....................
 (b)(2)(xiv).
63.(10)(b)(3)...............  Yes.                  ....................
63.10(c)(1) through (9).....  Yes.                  ....................
63.10(c)(10) and (11).......  No..................  See Sec.  Sec.
                                                     63.850(e)(4)(xvi)
                                                     and (xvii) for
                                                     recordkeeping of
                                                     malfunctions.
63.10(c)(12) through (c)(14)  Yes.                  ....................
63.10(c)(15)................  No.                   ....................
63.10(d)(1) through (4).....  Yes.                  ....................
63.10(d)(5).................  No..................  See Sec.
                                                     63.850(d)(2) for
                                                     reporting of
                                                     malfunctions.
63.10(e) and (f)............  Yes.                  ....................
63.11.......................  No..................  Flares will not be
                                                     used to comply with
                                                     the emission
                                                     limits.
63.12 through 63.15.........  Yes.                  ....................
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[FR Doc. 2011-29881 Filed 12-5-11; 8:45 am]
BILLING CODE 6560-50-P