------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Actual..............................  Risks for Point Sources            2       0.010           3,000               0        0.03  Developmental..............         0.3  Arsenic.
                                       Only.
                                      Risks for Nonpoint                20        0.12       4,000,000           9,000         0.3  Developmental..............           3  Arsenic.
                                       Emissions & Point
                                       Sources.
Allowables..........................  Risks for Point Sources           30        0.13       4,000,000          11,000         0.3  Developmental..............
                                       Only.
                                      Risks for Nonpoint                50        0.24       4,000,000          90,000         0.7  Developmental..............
                                       Emissions & Point
                                       Sources.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  Table 4--Estimated Percent Contribution to the MIR for All Emissions
     Sources at the Example Facility Based on EPA's Estimated Actual
                                Emissions
------------------------------------------------------------------------
  Estimated percent  contribution to the
       total MIR of 20-in-1 million               Emissions source
------------------------------------------------------------------------
50........................................  BF casthouse (fugitives).
21........................................  BOPF shop (fugitives).
9.........................................  BF bell leaks (fugitives).
8.........................................  All point sources combined.
5.........................................  BF planned openings
                                             (intermittent).
4.........................................  BF unplanned openings/Slips
                                             (intermittent).
2.........................................  BF slag handling
                                             (fugitives).
2.........................................  BF beaching (intermittent,
                                             fugitive).
100.......................................  Total.
------------------------------------------------------------------------

    As described in section III.C.8 above, there are uncertainties in
the EPA's emissions estimates for the nonpoint sources used in the
example facility risk analysis since the estimates are based on
emission factors (some of which are relatively old) and many
assumptions, especially where emission factors from other processes are
used as estimates for UFIP sources. In addition, the example facility
had a higher arsenic-to-PM ratio for the BF in the 2011 ICR data
compared to other facilities. Subsequently, the American Iron and Steel
Institute (AISI) provided additional, more recent test data for the
example facility that suggest arsenic emissions are lower than the
level we had estimated based on the 2011 ICR data that we used in our
analysis (see Paul Balserak, 2019, citation in footnote 18). Therefore,
we conclude the emissions used in our risk assessment are conservative
(upper-end) estimates. This uncertainty also leads us to conclude that
the risk results that include nonpoint sources are a qualitative
indicator of the potential risk, rather than a true quantitative
analysis, that may be higher than the actual risk due to assumptions
about the level of emissions from nonpoint sources. These assumptions
and uncertainties are explained in the memorandum titled Development of
Emissions Estimates for Fugitive or Intermittent HAP Emission Sources
for an Example Integrated Iron and Steel Manufacturing Facility for
Input to the RTR Risk Assessment, available in the docket to this rule
and summarized above.
    In addition to supplying new test data, the AISI also conducted
their own risk analysis for the same example facility using the same
input data (e.g., stack release parameters, fugitive source
characteristics, latitude/longitude data for each emissions source,
receptor information, etc.), the same model and following the same
modeling analysis approach that the EPA used, except that

AISI used the newer 2018 test data instead of the 2011 ICR test data
that the EPA used. The new test data and AISI risk results are
described in the February 2019 AISI document (see Paul Balserak, 2019),
which is available in the docket for this action.
    We did not have adequate time to complete an extensive review of
the new test data, revise our model input files, and redo our risk
analysis before proposal; therefore, we have not yet evaluated the full
extent of how the new data will affect the overall results of the
example facility risk assessment. Nevertheless, we expect that once we
incorporate the new test data into our analyses and rerun our risk
model, the risks will be lower than the risk estimates presented in
Table 3 above. The results presented by AISI (which are presented in
Table 5) indicate the MIR when the UFIP emissions are included could be
about half the estimated value in the EPA's risk characterization
presented above (i.e., 8-in-1 million compared to the EPA's estimate of
20-in-1 million) and that population risks also could be substantially
lower than those presented above in this preamble, with an estimated
500,000 people with risks greater than or equal to 1-in-1 million
compared to the estimate of 4,000,000 in the EPA's risk
characterization.

       Table 5--Comparison of the Inhalation Risk Estimates for Point and Nonpoint Sources for Example Facility Based on the EPA and AISI Analyses
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Inhalation chronic cancer risks
                                                         -----------------------------------------------------------------------------------------------
                                                                MIR (in 1 million)         Population with risks >1-in-1  Population with risks  >10-in-
                                                         --------------------------------             million                        1 million
                        Emissions                                                        ---------------------------------------------------------------
                                                          Based on EPA's     Based on                        Based on                        Based on
                                                           risk analysis    AISI's risk   Based on EPA's    AISI's risk   Based on EPA's    AISI's risk
                                                                             analysis      risk analysis     analysis      risk analysis     analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Actual..................................................              20               8       4,000,000         500,000           9,000               0
Allowables..............................................              50              20       4,000,000              NA          90,000              NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available.

    Despite uncertainties in the individual nonpoint emission estimates
and the range of estimated potential risks reflected in Table 5,
monitor data near the example facility indicate that both the EPA and
AISI analyses better predict levels of metal HAP (e.g., arsenic and
lead) when nonpoint emissions are included. The comparisons of modeled
results to ambient monitoring data are described in the EPA's technical
memorandum titled Development of Emissions Estimates for Fugitive or
Intermittent HAP Emission Sources for an Example Integrated Iron and
Steel Manufacturing Facility for Input to the RTR Risk Assessment, and
in the February 2019 AISI risk assessment document,\18\ both available
in the docket for this proposed rule.
    In summary, comparing the EPA's risk model results for UFIP
emissions plus point sources to the risk model results for point
sources alone for the example facility, the MIR based on actual
emissions from only point sources was approximately an order of
magnitude lower than the MIR obtained when UFIP emissions were included
(about 2-in-1 million compared to about 20-in-1 million). The AISI
analysis indicates the MIR based on actual emissions from only point
sources also was approximately an order of magnitude lower than the MIR
obtained when UFIP emissions were included (about 0.7-in-1 million
compared to about 8-in-1 million). A similar relationship is seen for
noncancer HI in the EPA's analysis, with 0.03 HI for point sources only
as compared to 0.3 HI for point sources plus UFIP emissions. As shown
in Tables 3 and 5 of this preamble, population risks also increased
significantly when including UFIP emissions with actual point source
emissions. For both actual and allowable emission scenarios, the
increase in estimated risk when including UFIP emissions was primarily
a result of the fugitive HAP metal emissions from BF and BOPF
operations. However, as described above, there are uncertainties in the
UFIP emissions estimates. Further details on the EPA's risk analysis
for the UFIP and other emissions can be found in the document titled
Residual Risk Assessment for the Integrated Iron and Steel
Manufacturing Source Category in Support of the Risk and Technology
Review 2019 Proposed Rule, available in the docket for this action.
    It is important to note that we did not estimate the nonpoint
emissions for any facilities other than the example facility in the
source category. Therefore, we did not estimate the risks due to
nonpoint emissions from those facilities. Because the fugitive
emissions from UFIP sources were estimated from production-based
emission factors, we made a reasonable assumption that the facility
that produces the most product would be estimated to have the highest
fugitive emissions; hence, the selection of the example facility to run
the risk model for UFIP emissions because it has the highest production
rate in the source category. Additionally, actual nonpoint emissions
could be affected to some unknown extent by the quality of equipment
and operational practices at each facility.
    Nevertheless, by evaluating the risk results from the example
facility (for both nonpoint and point sources) along with the risk
results for the point sources for all 11 facilities, it appears that
the inclusion of nonpoint sources for risk assessment at all other
facilities potentially could result in an MIR slightly greater than 70-
in-1 million based on allowable emissions, but less than 90-in-1
million. We derived this upper bound worst-case potential risk by
taking the MIR for another facility, which had the highest MIR based on
point source allowable emissions among all 11 facilities (i.e., MIR of
70-in-1 million from Table 2), and assumed that the risks due to
nonpoint sources at this facility would be less than the 20-in-1
million MIR we estimated for the example facility, because the other
facility has much lower production rate compared to the example
facility. Thus, we conclude that the estimated upper end MIR based on
allowable emissions for the source category could be slightly more than
70-in-1 million but less than 90-in-1 million. We are asking for
comments on the potential risk from UFIP sources, as described above,
and the impact that the potential additional risk could have on the
risk for the source category and overall acceptability of the risk for
the source category.

4. Multipathway Risk Screening Results
    Potential multipathway health risks under a fisher and gardener
scenario were evaluated using a three-tier screening assessment of the
PB-HAP emitted by point sources at facilities in this source category.
All 11 facilities have reported emissions of carcinogenic PB-HAP
(dioxins/furans, arsenic, and POM) and non-carcinogenic PB-HAP (cadmium
and mercury) that exceed the Tier 1 SV of 1 for the fisher/farmer
scenario. For facilities that exceeded a Tier 1 multipathway SV of 1,
we used additional facility-specific information to perform an
assessment through Tiers 2 and 3 and a site-specific analysis, as
necessary, to determine the maximum chronic cancer and noncancer
multipathway health risks for the source category. For cancer, the
highest Tier 3 SV was 200 (arsenic and dioxins/furans), and there were
seven facilities with Tier 3 SV greater than 1. For noncancer, the
highest Tier 3 SV was 2 (mercury and cadmium), and there was one
facility with Tier 3 SV greater than 1.
    An exceedance of a SV in any of the tiers cannot be equated with a
risk value or an HQ (or HI). Rather, it represents a high-end estimate
of what the risk or hazard may be. For example, a SV of 2 for a non-
carcinogen can be interpreted to mean that we are confident that the HQ
would be lower than 2. Similarly, a SV of 200 for a carcinogen means
that we are confident that the risk is lower than 200-in-1 million. Our
confidence comes from the conservative, or health-protective,
assumptions encompassed in the screening tiers: We choose inputs from
the upper end of the range of possible values for the influential
parameters used in the screening tiers; and we assume that the exposed
individual exhibits ingestion behavior that would lead to a high total
exposure.
    To further evaluate the potential multipathway risks, we conducted
a site-specific analysis of three facilities that are located in close
proximity to each other: ArcelorMittal-Indiana Harbor facility, U.S.
Steel Gary Works, and ArcelorMittal-Burns Harbor. All three facilities
also have sinter plants that emit dioxins/furans and are close to water
bodies. These candidate sites also were selected because of their
exceedances of the cancer SV, where arsenic and dioxins/furans under
the fisher and gardener scenarios had the highest exceedances for the
source category, and because of their exceedances of the tiered
noncancer SV, where mercury and cadmium under the fisher scenario had
the highest exceedances for the source category. We expect that the
exposures we assessed are among the highest that might be encountered
in this source category, based on combination of the magnitude of HAP
emissions and the density of the population in the regions surrounding
the facilities.
    The site-specific analysis for the fisher scenario resulted in an
estimated maximum excess individual cancer risk of about 40-in-1
million (due to dioxin/furan emissions from sinter plants) and the
gardener (rural) scenario resulted in an estimated maximum excess
individual cancer risk of about 20-in-1 million for arsenic and
dioxins/furans. The site-specific multipathway assessment for the
fisher scenario produced a noncancer HQ of 0.1 for cadmium and 0.5 for
mercury. The protocol for developing the refined site-specific
multipathway assessment, input data, assumptions, and detailed results
are presented in the document titled Residual Risk Assessment for the
Integrated Iron and Steel Manufacturing Source Category in Support of
the Risk and Technology Review 2019 Proposed Rule, available in the
docket for this action.
    In evaluating the potential for multipathway effects from emissions
of lead, we compared modeled annual lead concentrations to the primary
NAAQS for lead (0.15 [micro]g/m\3\). The highest annual lead
concentration of 0.004 [micro]g/m\3\ is well below the NAAQS for lead,
indicating a low potential for multipathway impacts of concern due to
lead. Multipathway risks were not explicitly calculated with the
additional estimated actual UFIP. However, based upon the increase in
certain metal emissions (arsenic and mercury), we could expect these
risks to increase as well, although not linearly with emission changes.
5. Environmental Risk Screening Results
    As described in section III.C of this document, we conducted an
environmental risk screening assessment for the Integrated Iron and
Steel Manufacturing source category for the following pollutants:
Arsenic, cadmium, dioxins/furans, HCl, lead, mercury (methyl mercury
and mercuric chloride), and POM.
    In the Tier 1 screening analysis for PB-HAP (other than lead, which
was evaluated differently), arsenic emissions at two facilities had
exceedances for the surface soil threshold level (plant communities)
and the surface soil No Observed Adverse Effect Level (NOAEL) (avian
ground insectivores) by a maximum SV of 4. Cadmium emissions at nine
facilities had Tier 1 exceedances for the surface soil NOAEL (mammalian
insectivores and avian ground insectivores), the fish NOAEL (avian
piscivores and mammalian piscivores), the sediment community no-effect
level, and the water-column community threshold level by a maximum SV
of 50. Dioxins/furans emissions at three facilities had Tier 1
exceedances for the surface soil NOAEL (mammalian insectivores) by a
maximum SV of 600. Divalent mercury emissions at 11 facilities had Tier
1 exceedances for the surface soil threshold level (invertebrate and
plant communities) and the sediment threshold level by a maximum SV of
60. Divalent mercury emissions, and subsequent methylation and
formation of methyl mercury in biota, at the 11 facilities resulted in
Tier 1 exceedances for the surface soil NOAEL (avian ground
insectivores and mammalian insectivores) and the fish NOAEL (avian
piscivores) by a maximum SV of 90. POM emissions at two facilities had
Tier 1 exceedances for the sediment no-effect level by a maximum SV of
5.
    A Tier 2 screening assessment was performed for arsenic, cadmium,
dioxins/furans, divalent mercury, methyl mercury, and POM emissions.
Arsenic, divalent mercury, and POM emissions had no Tier 2 exceedances
for any ecological benchmark. Emissions from five facilities impact one
lake (Chubb Lake), which caused an exceedance of the Tier 2 screen for
the fish NOAEL (avian piscivores) by a maximum SV of 2 for both cadmium
and divalent mercury. Dioxins/furans emissions from one facility
exceeded the Tier 2 screen for the surface soil, NOAEL (mammalian
insectivores) by a maximum SV of 4. This exceedance is based on the
area-weighted average dioxins/furans concentration in the soils around
this facility, for which 100 percent of the modeled soil area exceeded
the Tier 2 screen. None of the other dioxin benchmarks evaluated were
exceeded in the Tier 2 screen, including the NOAEL for common merganser
and the NOAEL for mink.
    A site-specific assessment, incorporating plume rise and hour-by-
hour concentrations, was conducted for the dioxins/furans emissions
from this facility. In the site-specific assessment, the area-weighted
average dioxins/furans concentration in the soils around the facility
did not exceed any benchmark. However, approximately 39 percent of the
modeled soil area did exceed the NOAEL benchmark for mammalian
insectivores (shrew) (exceedance areas had an area-weighted average
exceedance of 3). However, none of the other 12 ecological benchmarks
evaluated for dioxins/

furans showed any exceedances. This includes the following other NOAEL
benchmarks: NOAEL for fish-eating birds (common merganser), NOAEL for
fish-eating mammals (mink), and a lake benthic sediment no-effect
level. Since the area-weighted-average dioxins/furans soil
concentration did not exceed any benchmark and only one NOAEL of the
three NOAELs evaluated showed any exceedance of a portion of the
modeled area, we do not expect a significant and widespread adverse
effect as a result of the dioxins/furans emissions from this source
category. The analysis estimated no exceedances of the secondary lead
NAAQS. For HCl, the average modeled concentration around each facility
(i.e., the average concentration of all off-site data points in the
modeling domain) did not exceed any ecological benchmark. In addition,
each individual modeled concentration of HCl (i.e., each off-site data
point in the modeling domain) was below the ecological benchmarks for
all facilities.
    Based on the results of the environmental risk screening analysis,
we do not expect an adverse environmental effect as a result of HAP
emissions from this source category.
6. Facility-Wide Risk Results
    Based on facility-wide emissions of point sources and noncategory
sources, the estimated cancer MIR is 80-in-1 million, mainly driven by
emissions from coke ovens, which are from noncategory sources, i.e.,
not part of the Integrated Iron and Steel Manufacturing source
category. The total estimated cancer incidence from the facility-wide
analysis is 0.1 excess cancer cases per year, or one excess case every
9 years. Approximately 1,800,000 people were estimated to have cancer
risks at or above 1-in-1 million, and 67,000 of these people were
estimated to have cancer risks at or above 10-in-1 million, from
exposure to HAP emitted from both sources that are part of the
Integrated Iron and Steel Manufacturing source category and sources
that are not part of the source category at the 11 facilities in the
source category. The maximum facility-wide TOSHI for the source
category is estimated to be 0.8 (for the neurological HI) driven by
emissions of manganese compounds from sources that are not part of the
source category. Emissions of noncategory sources are described in the
technical memorandum titled Integrated Iron and Steel Data Summary for
Risk and Technology Review, available in the docket to this rule, that
includes a description of all the emissions and process data used in
this proposed rule along with any assumptions that were made.
7. What demographic groups might benefit from this regulation?
    To examine the potential for any environmental justice issues that
might be associated with the source category, we performed a
demographic analysis, which is an assessment of risks to individual
demographic groups of the populations living within 5 km and within 50
km of the facilities. In the analysis, we evaluated the distribution of
HAP-related cancer and noncancer risks from the Integrated Iron and
Steel Manufacturing source category point sources across different
demographic groups within the populations living near facilities.\23\
Note that we did not do this type of analysis for the UFIP emissions
because we only estimated UFIP emissions for one facility.
---------------------------------------------------------------------------

    \23\ Demographic groups included in the analysis are: White,
African American, Native American, other races and multiracial,
Hispanic or Latino, children 17 years of age and under, adults 18 to
64 years of age, adults 65 years of age and over, adults without a
high school diploma, people living below the poverty level, people
living two times the poverty level, and linguistically isolated
people.
---------------------------------------------------------------------------

    The results of the demographic analysis are summarized in Table 6
below. These results, for various demographic groups, are based on the
estimated risk from actual emissions from point sources for the
population living within 50 km of the facilities.

               Table 6--Integrated Iron and Steel Manufacturing Demographic Risk Analysis Results
----------------------------------------------------------------------------------------------------------------
                                                                         Population with
                                                                      cancer risk at or at     Population with
                                                                         or above 1-in-1      chronic HI at or
                     Item                            Nationwide          million due to        above 1 due to
                                                                       integrated iron and   integrated iron and
                                                                       steel manufacturing   steel manufacturing
----------------------------------------------------------------------------------------------------------------
Total Population..............................           317,746,049                64,158                     0
----------------------------------------------------------------------------------------------------------------
                                          White and Minority by Percent
----------------------------------------------------------------------------------------------------------------
White.........................................                    62                    63                     0
Minority......................................                    38                    37                     0
----------------------------------------------------------------------------------------------------------------
                                               Minority by Percent
----------------------------------------------------------------------------------------------------------------
African American..............................                    12                    29                     0
Native American...............................                   0.8                   0.1                     0
Hispanic or Latino includes white and                             18                     4                     0
 nonwhite)....................................
Other and Multiracial.........................                     7                     4                     0
----------------------------------------------------------------------------------------------------------------
                                                Income by Percent
----------------------------------------------------------------------------------------------------------------
Below Poverty Level...........................                    14                    23                     0
Above Poverty Level...........................                    86                    77                     0
----------------------------------------------------------------------------------------------------------------
                                              Education by Percent
----------------------------------------------------------------------------------------------------------------
Over 25 and without High School Diploma.......                    14                    12                     0
Over 25 and with a High School Diploma........                    86                    88                     0
----------------------------------------------------------------------------------------------------------------

                                       Linguistically Isolated by Percent
----------------------------------------------------------------------------------------------------------------
Linguistically Isolated.......................                     6                   0.6                     0
----------------------------------------------------------------------------------------------------------------

    The results of the Integrated Iron and Steel Manufacturing source
category demographic analysis indicate that point source emissions from
the source category expose approximately 64,000 people to a cancer risk
at or above 1-in-1 million and zero people to a chronic noncancer HI
greater than or equal to 1. The percentages of the at-risk population
in each demographic group (except for African American and Below
Poverty Level) are similar to or lower than their respective nationwide
percentages. The African American population exposed to a cancer risk
at or above 1-in-1 million due to Integrated Iron and Steel
Manufacturing emissions is more than three times the national average.
Likewise, populations living ``Below Poverty Level'' exposed to cancer
risk at or above 1-in-1 million is nearly twice the national average.
    The methodology and the results of the demographic analysis are
presented in a technical report, Risk and Technology Review--Analysis
of Demographic Factors for Populations Living Near Integrated Iron and
Steel Manufacturing Facilities, available in the docket for this
action.

B. What are our proposed decisions regarding risk acceptability, ample
margin of safety, and adverse environmental effect?

    In this section, we discuss the results of our analysis of risk
from point sources and our analysis of risk from point and nonpoint
sources at the example facility. We also discuss our proposed finding
of acceptability and our ample margin of safety analysis.
1. Risk Acceptability
    As noted in section II.A of this preamble, the EPA sets standards
under CAA section 112(f)(2) using ``a two-step standard-setting
approach, with an analytical first step to determine an `acceptable
risk' that considers all health information, including risk estimation
uncertainty, and includes a presumptive limit on MIR of approximately
1-in-10 thousand.'' (54 FR 38045, September 14, 1989). In this
proposal, the EPA estimated risks based on actual and allowable
emissions from Integrated Iron and Steel Manufacturing sources, and we
considered these in determining acceptability.
    The estimated inhalation cancer risk to the individual most exposed
to actual emissions from the source category based on modeling point
source emissions for all 11 facilities is 10-in-1 million. The
estimated incidence of cancer due to inhalation exposures due to the
point sources for the source category is 0.03 excess cancer cases per
year, or one excess case every 33 years. We estimate that approximately
64,000 people face an increased cancer risk greater than or equal to 1-
in-1 million due to inhalation exposure to HAP emissions from the point
sources for this source category. The Agency estimates that the maximum
chronic noncancer TOSHI from inhalation exposure due to point sources
(only) for this source category is 0.1. The screening assessment of
worst-case acute inhalation impacts due to point sources (only)
indicates a maximum HQ of 0.3 (due to arsenic) based on the REL. With
regard to multipathway human health risks, we estimate the cancer risk
for the highest exposed individual is 40-in-1 million (due to dioxins/
furans emissions from sinter plants) and the maximum chronic HI is less
than 1 for all the PB HAP. Although we did not assess multipathway risk
for the example facility, the highest exposed individual for dioxins/
furans in the point source modeling was not due to the example facility
and none of the nonpoint sources are expected to include dioxin/furans
emissions.
    Based on allowable emissions, the estimated inhalation cancer risk
to the individual most exposed from point sources for the source
category would be 70-in-1 million and the estimated incidence of cancer
due to inhalation exposures to these allowable emissions would be 0.3
excess cancer cases per year, or one excess case every 3 years. An
estimated 6 million people would face an increased cancer risk greater
than or equal to 1-in-1 million due to inhalation exposure to allowable
HAP emissions from this source category. The maximum chronic noncancer
TOSHI from inhalation exposure would be 0.9 based on allowable
emissions.
    With regard to the estimated risks due to actual emissions from
nonpoint and point sources for the example facility, the estimated
inhalation cancer risk to the individual most exposed to actual
emissions for the example facility when nonpoint sources were included
in the EPA's risk analysis increased from 2-in-1 million to 20-in-1
million. The population exposed to risks greater than or equal to 1-in-
1 million increased from 3,000 to 4,000,000,\24\ and the population
exposed to risks greater than or equal to 10-in-1 million increased
from 0 to 9,000 due to increase in the estimated HAP emissions from 3
tpy to 53 tpy. The maximum chronic noncancer TOSHI from inhalation
exposures remained at less than 1, but the acute HQ increased from 0.3
to 3 based on the REL (for arsenic). Based on allowable emissions, the
estimated inhalation cancer risk to the individual most exposed
increased from 30-in-1 million to 50-in-1 million with nonpoint
sources. Thus, if nonpoint emissions were quantified for the entire
source category, the source category risks presented in this section
(based on point sources only) including the number of individuals with
cancer risk exceeding 1-in-1 million would be expected to increase for
each facility. Although it is problematic to estimate from the results
presented here what the increase in risk might be for each facility in
the entire industry without quantifying nonpoint emissions for each
facility, based upon results from the example facility, we conclude
that it is likely that the cancer and noncancer risks at other
facilities would be less than 90-in-1 million and

the maximum chronic noncancer HI would be less than 1.
---------------------------------------------------------------------------

    \24\ The large affected population reflects the Greater Chicago
area, which is in close proximity to the example facility. Metal HAP
emissions at the example facility increased by a factor of 15 when
UFIP emissions estimates were added to point source emissions; this
increase is reflected in the estimated risk impacts for the example
facility.
---------------------------------------------------------------------------

    In determining whether risks are acceptable for this source
category, the EPA considered all available health information and risk
estimation uncertainty as described above. The risk results indicate
that the inhalation cancer risks to the individual most exposed may be
more than 70-in-1-million but less than 90-in-1 million, as a worst
case, considering the highest allowable risk due to point sources among
the industry facilities plus the conservative estimate of risk from
UFIP, which is less than the presumptive limit of acceptability of 100-
in-1 million,\25\ and also considering the uncertainties in the example
facility analysis, as described above in section III.C.8.a. There are
no facilities with an estimated maximum chronic noncancer HI greater
than or equal to 1 from point sources. The maximum acute HQ for all
pollutants is less than 1 when we only consider point source emissions,
and up to 3 based on the REL for arsenic when including exposures to
estimated emissions from nonpoint emissions at the example facility.
For the acute screening analyses, to better characterize the potential
health risks associated with estimated worst-case acute exposures to
HAP, the EPA examines a wider range of available acute health metrics
than is done for chronic risk assessments. This is in acknowledgement
that there are generally more data gaps and uncertainties in acute
reference values than there are in chronic reference values. By
definition, the acute REL represents a health-protective level of
exposure, with effects not anticipated below those levels, even for
repeated exposures; however, the level of exposure that would cause
health effects is not specifically known. As the exposure concentration
increases above the acute REL, the potential for effects increases. In
addition, the acute screening assessment includes the conservative
(health protective) assumptions that every process releases its peak
hourly emissions at the same hour, that the near worst-case dispersion
conditions occur at that same hour, and that an individual is present
at the location of maximum concentration for that hour. Further, the HQ
value was not refined to an off-site location, which, in many cases,
may be significantly lower than that estimated at an on-site receptor.
Thus, because of the conservative nature of the acute inhalation
screening assessment as well as the uncertainty in the nonpoint
emission estimates, there is low probability that the maximum HQ of 3
is associated with adverse health effects in the industry as a whole.
---------------------------------------------------------------------------

    \25\ See Benzene NESHAP (54 FR 38044, September 14, 1989)
discussion above in section II.A of this proposal.
---------------------------------------------------------------------------

    Considering all of the health risk information and factors
discussed above, including the uncertainties regarding our estimates of
nonpoint emissions discussed in section III of this preamble, the EPA
proposes that the risks are acceptable. The estimated cancer risks are
below the presumptive limit of acceptability and the noncancer results
indicate there is minimal likelihood of adverse noncancer health
effects due to HAP emissions from this source category. We request
comments on this proposed determination of acceptability.
2. Ample Margin of Safety Analysis and Potential Controls
    We next considered whether the existing MACT standards provide an
ample margin of safety to protect public health. In the ample margin of
safety analysis, we evaluated the cost and feasibility of available
control technologies and other measures (such as work practices) that
could be applied to the source category to further reduce the risks due
to emissions of HAP. For purposes of the ample margin of safety
analysis, after we evaluated these controls and measures and identified
possible regulatory options based on this evaluation, we estimated the
reductions in risks that would occur through adoption of these options
for both actual and allowable emissions.
a. Point Sources
    The point sources at Integrated Iron and Steel Manufacturing
facilities are already well controlled with baghouses and scrubbers.
However, as part of the ample margin of safety assessment, we evaluated
the following additional technologies for controlling point source
emissions to further reduce risk from these sources, taking into
consideration costs, energy, safety and other relevant factors. First,
we evaluated the installation of a wet electrostatic precipitator (ESP)
on the exhaust of the current air pollution control devices for the BF
casthouse primary units to reduce chromium VI and arsenic emissions,
respectively. We also evaluated the installation of activated carbon
injection (ACI) systems onto current control devices for the sinter
plant windbox to reduce emissions of dioxins/furans. Table 7 below
shows the estimated costs, and emission and risk reductions with
installation of these controls.

                    Table 7--Results of Ample Margin of Safety Analysis for Point Source Risk
----------------------------------------------------------------------------------------------------------------
                                                                    By HAP and Unit
                                      --------------------------------------------------------------------------
                                        Chromium VI (actuals)     Arsenic (allowable)         Dioxins/furans
                 Item                 --------------------------------------------------    (actuals, as TEQ)
                                                                                ------------------------
                                                  BF                      BOPF                 Sinter plant
----------------------------------------------------------------------------------------------------------------
                                                 Industry Costs
----------------------------------------------------------------------------------------------------------------
Capital..............................  $476,538,529...........  $793,465,144...........  $781,286.
Annual...............................  $62,065,611............  $103,342,953...........  $1,849,781.
----------------------------------------------------------------------------------------------------------------
                                                Emissions Removed
----------------------------------------------------------------------------------------------------------------
                                       3.29E-02 tpy...........  2.25 tpy...............  1.97E-02 lb/yr.
----------------------------------------------------------------------------------------------------------------
                               Cost Effectiveness [Annual Costs/Emissions Removed]
----------------------------------------------------------------------------------------------------------------
Individual HAP.......................  $943,217/lb............  $22,918/lb.............  $94,006,541/lb.

                                       $1.9 trillion/ton......  $46 million/ton........  $188 trillion/ton.
----------------------------------------------------------------------------------------------------------------
                                                    Risk MIR
----------------------------------------------------------------------------------------------------------------
Before Control.......................  10.....................  70.....................  40.
After Control........................  <1.....................  4......................  <1.
----------------------------------------------------------------------------------------------------------------

    Although the MIR could be reduced from 10-in-1 million, 70-in-1
million, and 40-in-1 million for BF chromium actual emissions, BOPF
arsenic allowable emissions, and sinter plant dioxins/furans actual
emissions as toxic equivalents (TEQ),\26\ respectively, we are not
proposing any of these control scenarios because of the relatively high
capital costs and annualized costs. These controls are not considered
cost effective, where cost effectiveness estimates are determined to be
$1.9 trillion/ton ($940,000/pound(lb)), $46 million/ton ($23,000/lb),
and $188 trillion/ton ($94 million/lb) for BF chromium, BOPF arsenic,
and sinter plant dioxins/furans, respectively. For details of this
analysis, see the technical document titled Ample Margin of Safety for
Point Sources in the II&S Industry, available in the docket to this
rule, that describes the costs of additional control of BF chromium,
BOPF arsenic, and sinter plant dioxin/furans.
---------------------------------------------------------------------------

    \26\ From the 2005 World Health Organization (WHO) toxicity
equivalence factors. See Recommended Toxicity Equivalence Factors
(TEFs) for Human Health Risk Assessments of 2,3,7,8-
Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds. Publication
No. EPA/100/R-10/005. U.S. EPA, Washington, DC. 2010.
---------------------------------------------------------------------------

b. Nonpoint Sources
    In addition to the control options assessed for point sources, we
identified work practices that could achieve HAP reductions from the
seven nonpoint sources, such as more frequent measurements (e.g.,
opacity, internal furnace conditions), increased maintenance, applying
covers on equipment, developing operating plans to minimize emissions,
optimizing positioning of ladles with respect to hood faces, and
earlier repair of equipment. We evaluated work practices for these
seven nonpoint sources, because the nature of these fugitive and
intermittent emissions are such that they are not emitted through a
conveyance designed and constructed to capture these pollutants. The
work practices are described in more detail below. We request comments
on these work practices and related information included below.
    As shown in Table 4 (above), the two nonpoint sources that present
the highest contribution to the MIR are the BF casthouse and BOPF shop,
which are currently regulated by opacity limits in the rule. These two
nonpoint sources account for an estimated 71 percent of the 20-in-1-
million MIR at the example facility. The other five nonpoint sources
(BF slag handling and storage, BF bell leaks, BF (bleeder valve)
planned openings, BF (bleeder valve) unplanned openings, and BF iron
beaching), when combined, account for about 22 percent of the 20-in-1-
million MIR at the example facility.
    We evaluated two main options to reduce emissions and risks under
the ample margin of safety analysis under CAA section 112(f)(2).
Although we are not proposing standards based on either option, we are
requesting comments on the options. We ask for comments on the costs
and effectiveness of the work practices to reduce emissions; whether
these work practices should be viewed as viable methods to reduce
emissions and, therefore, risk from these nonpoint sources; and whether
further control of fugitive and/or intermittent emissions from these
nonpoint sources by implementation of the work practices, pursuant to
CAA section 112(h), should be required under the ample margin of safety
analysis for this source category.
    Option 1 would be to establish work practice standards for two of
the nonpoint sources (BF casthouse fugitives and BOPF shop fugitives),
which pose the greatest contribution to the MIR. Potential work
practices for each of these two fugitive sources include the following:
    Potential work practices for the BF casthouse fugitives:
     Keep runner covers in place at all times except when
runner or cover is being repaired or removed for inspection purposes
(2-hour repair or observation limit);
     Develop and operate according to a ``BF Casthouse
Operating Plan'' to minimize fugitive emissions and detect openings and
leaks;
     Measure opacity frequently during the tapping operation
(e.g., during four taps per month) with all openings closed (except for
roof monitor) using EPA Method Alt-082 (camera) or EPA Method 9; and
     Keep doors and other openings, except roof monitors,
closed during all transfer operations to extent feasible and safe.
    Potential work practices for the BOPF shop fugitives:
     Develop and operate according to a ``BOPF Shop Operating
Plan'' to minimize fugitive emissions and detect openings and leaks;
     BOPF Shop Operating Plan may include:
    [cir] List of all events that generate visible emissions (VE),
including slopping, and steps company will take to reduce incidence
rate;
    [cir] Minimize hot iron pour/charge rate (minutes);
    [cir] Schedule of regular inspections of BOPF shop structure for
openings and leaks to the atmosphere;
    [cir] Optimize positioning of hot metal ladles with respect to hood
face and furnace mouth;
    [cir] Optimize furnace tilt angle during charging;
    [cir] Keep all openings, except roof monitors, closed, especially
during transfer, to extent feasible and safe;
    [cir] Use higher draft velocities to capture more fugitives at a
given distance from hood, if possible; and
    [cir] Monitor opacity periodically (e.g., once per month) from all
openings with EPA Method Alt-082 (camera) or with EPA Method 9.
    We estimate these work practices would achieve a range of 50- to
90-percent reduction in fugitive emissions from these sources, based on
EPA judgement as to the potential

effectiveness of the work practices. With regard to reductions in
risks, we developed a model input file to reflect the estimated
emissions reductions that would be achieved under the Option 1 scenario
and performed a post-control modeling scenario to estimate risk
reductions. For the post-control scenario, we assumed the work
practices would achieve 70-percent reduction in emissions (the midpoint
between 50 and 90 percent). Based on this modeling assessment, we
estimate Option 1 would reduce the MIR from 20-in-1 million to about
10-in-1 million for the example facility, the estimated population with
risks greater than or equal to 1-in-1 million would decrease from
4,000,000 to 1,500,000, and the estimated population with risks greater
than or equal to 10-in-1 million would decrease from 9,000 to 800. In
addition, the maximum acute HQ would decrease from 3 to 2. This option
also would achieve reductions in PM at or below 2.5 micrometers
(PM2.5). We request comments on these estimated reductions.
    We estimate the total capital costs of Option 1 for the source
category would be about $1.4 million and annualized costs would be
about $1.7 million per year, with a cost effectiveness value of
approximately $10,000/ton HAP corresponding to an estimate of 173 tons
of HAP reductions. This estimate is based on cost estimates for
individual emission units that were projected to the entire industry
based on the number of units of each type at each facility. For details
on these cost estimates, see the technical memorandum titled Cost
Estimates and Other Impacts for the Integrated Iron and Steel Risk and
Technology Review, available in the docket to this proposed rule, that
describes the costs estimated for implementation of work practices to
control emissions from nonpoint sources, the estimated emission
reductions of HAP (and PM) at nonpoint sources with implementation of
the work practices, and the cost effectiveness of the work practices in
terms of estimated cost per ton of HAP (and PM) removed. We request
comments on these cost estimates.
    Option 2 would be to establish work practice standards for all
seven of the nonpoint sources described above. Potential work practices
for two of the seven sources, the BF casthouse and BOPF shop under
Option 2, would be the same as described above for Option 1. Potential
work practices for the other five out of seven nonpoint sources in
Option 2 include the following:

BF slag handling and storage operations
     Limit opacity to 10 percent, as 3-minute average; and
     Use of fog spray systems over pit area, applying spray
after each dump of slag and during all digging activities to extent
feasible and safe.

BF bell leaks (defined as opacity 10 percent for
45 seconds total)
     Limit opacity to 10 percent, as average of three
consecutive observations made 15 seconds to 5 minutes apart at any
location at the top of the furnace (i.e., small bell or inter-bell
relief valve);
     Observe BF top for VE monthly to identify beginning of
leaks; measure opacity if VE positive;
     Maintain metal seats of large and small bells to minimize
wear on seals; and
     Repair/replace seals within 4 months if fail to meet
limit.

BF planned openings
     Limit opacity to 10 percent, as 3-minute average;
     Develop and operate according to a ``Dirty Gas Bleeder
Valve Opening Plan'' to meet opacity limit;
     Idling preparation activities:
    [cir] Tap as much liquid (iron and slag) out of furnace as
possible;
    [cir] Remove fuel and/or stop fuel injection into furnace; and
    [cir] Establish and use lowest bottom pressure possible, according
to EPA-specified procedures.

BF unplanned openings (``slips'')
     Limit four slips/month;
    [cir] If exceed this limit (5th slip, 1st exceedance), develop and
operate according to a ``Slip Avoidance Plan'';
     Perform root cause analysis for 2nd and 3rd exceedance of
monthly limit (6th and 7th slip); modify plan as appropriate and safe
to decrease occurrence of slips; and
     At 4th exceedance of monthly limit (8th slip), install
additional devices to continuously measure/monitor material levels in
furnace (i.e., stockline), at a minimum of three locations, with alarms
to inform operators of static (i.e., not moving) stockline conditions
which increase the likelihood of slips. Also install/use instruments on
furnace to monitor temperature and pressure to help determine when a
slip has occurred. This information can help operators identify
potential problems and, therefore, adjust controls/actions to avoid
unplanned slips. These installations and monitoring would be required
within 3 months of 8th slip.

BF iron beaching
     Limit opacity to 20 percent, as 6-minute averages
continuously measured during entire beaching event;
     Minimize height, slope, and speed of beaching; and
     Use carbon dioxide shielding during beaching event; and/or
use full or partial (hoods) enclosures around beached iron.

 Table 8--Estimated Costs, Reductions, and Cost-effectiveness of Control of Nonpoint Sources via Work Practices
                             in the Integrated Iron and Steel Manufacturing Industry
----------------------------------------------------------------------------------------------------------------
                                                                                Cost
                                                                                HAP        effectiveness
                 Nonpoint source                   Capital costs   Annual costs     reductions       $/ton HAP
                                                                                tpy \a\         removed
----------------------------------------------------------------------------------------------------------------
BF Unplanned Openings...........................      $1,200,000        $197,747             3.1         $63,962
BF Planned Openings.............................  ..............          59,205             2.0          29,605
BF Bell Leaks...................................       5,000,000         555,771             4.3         130,680
BF Casthouse Fugitives..........................         960,000       1,183,981              36          32,821
BOPF Shop Fugitives.............................         480,000         500,541             137           3,665
BF Iron Beaching................................  ..............          99,494           0.042       2,392,593
Slag Handling & Storage.........................       1,100,000         451,602             2.9         157,167
                                                 ---------------------------------------------------------------
    Overall Total...............................       8,740,000       3,048,342             185          16,478
----------------------------------------------------------------------------------------------------------------

    We estimate the total capital costs of Option 2 for the source
category would be about $8.7 million and annualized costs would be
about $3 million per year, for a cost effectiveness of $16,000/ton HAP
corresponding to an estimate of

185 tons of HAP reductions. The estimated costs (capital and
annualized), reductions, and cost effectiveness for the work practices
for the seven individual UFIP sources are shown above in Table 8 and
discussed in detail in the technical memorandum titled Ample Margin of
Safety Analysis for Nonpoint Sources in the II&S Industry, available in
the docket for this rule. We assume these work practices would achieve
a range of 50- to 90-percent reduction in fugitive emissions.
    We request comments on these estimated reductions and cost
estimates. There may be energy savings from reducing leaks of BF gas
from bells, which is one of the work practices described above. We
solicit comment on the potential energy and related cost savings for
Integrated Iron and Steel Manufacturing facilities with implementation
of this work practice.
    The cost methodology and cost estimates for control of emissions
from the seven UFIP sources are described in detail in the technical
memorandum titled Cost Estimates and Other Impacts for the Integrated
Iron and Steel Risk and Technology Review, available in the docket to
this rule. We request comments on these cost estimates.
    With regard to reductions in risks, we developed a risk model input
file to reflect the estimated emissions reductions that would be
achieved under Option 2 and performed a post-control analysis to
estimate potential risk reductions. For the post-control scenario, we
assumed the work practices would achieve 70-percent reduction in
emissions (the midpoint between 50 and 90 percent). Based on this post-
control modeling assessment, we estimate Option 2 (i.e., work practices
for all seven nonpoint sources) would reduce the MIR from 20-in-1
million to about 9-in-1 million for example facility, the estimated
population with risks greater than or equal to 1-in-1 million would
decrease from 4,000,000 to 800,000, and the estimated population with
risks greater than or equal to 10-in-1 million would decrease from
9,000 to 0. Also, the maximum acute HQ would decrease from 3 to 0.9.
This option would also achieve reductions in PM2.5.
    We note that there are uncertainties in our assessment and are
requesting comments on this and any other issues that impact this
assessment. First, as described above, there are uncertainties in the
baseline UFIP emissions. Second, there are uncertainties in the
estimated reductions that would be achieved by the work practices
because we made assumptions regarding how much reduction would be
achieved with the work practices. Third, there are uncertainties in the
cost estimates because we made various assumptions about number of
labor hours, equipment needed, and other known factors. There may be
cost factors that are unknown to us at this time; we request comment on
any additional cost impacts.
c. Ample Margin of Safety Decisions
    Based on consideration of all the information described above,
including the risk results, costs, and uncertainties, we are proposing
that no additional standards are necessary under section 112(f) of the
CAA and that the current NESHAP provides an ample margin of safety.
This decision is based largely on the cost and cost effectiveness of
the point source controls and the uncertainties in the nonpoint source
assessment in terms of baseline emissions, costs of the work practices,
how much risk reduction they could achieve, and uncertainties regarding
potential effects of the work practices on the facilities' operations,
safety, and economics.
    We solicit comment on this proposed decision. We also solicit
comments, as well as additional information and data, on the work
practices and the two options described above. Specifically, we solicit
comment on the emissions estimates, cost estimates, cost savings,
estimated emissions reductions, control effectiveness, and any other
relevant information regarding the value or appropriateness of
incorporating work practices for UFIP sources into the NESHAP. We
solicit comment on whether Option 1 or Option 2 should be required for
these facilities, or some other combination of work practices. We also
solicit comments, data, and information on the specific seven work
practices, any issues they may present (e.g., safety, costs,
disruptions of operations, etc.) and whether or not they should be
included in the NESHAP and why.
    We also solicit comment on whether only opacity limits (similar to
opacity limits currently in the NESHAP for the BF casthouse and BOPF
shop fugitives) should be established for the other five UFIP (BF slag
handling and storage, BF bell leaks, BF planned openings, BF unplanned
openings, and BF iron beaching) without requiring any of the work
practices described above. For example, we are seeking comments on
whether it would be appropriate to establish opacity limits of 20
percent for all five of these UFIP or a subset of these five UFIP
sources. We also seek comments on whether it would be appropriate to
establish opacity limits of 20 percent for BF bell leaks and BF bleeder
valves (BF planned and unplanned openings) and 10 percent for BF iron
beaching and BF slag handling and storage that would be consistent with
requirements in some of the state implementation plans (SIP) for
criteria pollutants that apply to some of the existing facilities.
These opacity standards would ensure that these nonpoint sources in all
states do not have opacity above the SIP levels. Details of the SIP
requirements can be found in the technical memorandum titled Ample
Margin of Safety for Nonpoint Sources in the II&S Industry, located in
the docket for this rule and described above.
3. Adverse Environmental Effects
    Considering the results of our environmental risk screening, we do
not expect an adverse environmental effect as a result of HAP emissions
from this source category, and we are proposing that it is not
necessary to set a more stringent standard to prevent an adverse
environmental effect, taking into consideration costs, energy, safety,
and other relevant factors.

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

1. What are the results of our technology review for point sources?
    The emissions from point sources at Integrated Iron and Steel
Manufacturing facilities are controlled by baghouses, ESPs, scrubbers,
and fume/flame suppressants. For point sources, in addition to the
controls considered for point sources under the ample margin of safety
analysis above (in section IV.B), under the technology review, we
evaluated the cost effectiveness of upgrading fume/flame suppressants
used for control of fugitive PM and HAP metal emissions from BF to
control of emissions with baghouses, and process modifications to
further reduce dioxin/furan emissions from sinter plants. The
technology reviews of these two emissions sources are discussed below
and in detail in the technical memorandum titled Technology Review for
the Integrated Iron and Steel NESHAP, available in the docket to this
rule.
a. Upgrading Fume/flame Suppressants at Blast Furnaces to Baghouses
    Most emissions from the BF casthouse occur from tapping the molten
iron (product) and slag (waste) to remove these materials from the
furnace. Emissions occur at the taphole on the BF, from open troughs
(runners) that transport the iron and slag, from open

ladles that receive the molten iron, and open iron transport systems
(torpedo cars). These emissions are controlled in the Integrated Iron
and Steel Manufacturing industry in one of two fundamentally different
ways: fume and flame suppression techniques, or conventional
ventilation practices that route exhaust air to control devices such as
baghouses. Fume suppression consists of blowing natural gas over the
open equipment which retards vaporization and prevents emissions. With
flame suppression, the natural gas is ignited with accompanying oxygen
consumption that suppresses the formation of metal oxide emissions. In
more efficient control practices, local ventilation practices, such as
localized hooding and other area ventilation techniques, are used to
collect the emissions from the open BF equipment. Alternatively, the
casthouse may be totally enclosed and evacuated to a control device.
The use of fume/flame suppressants for control of fugitive BF casthouse
emissions is estimated to have 75-percent control, whereas control with
baghouses is estimated to have 95-percent control.
    There are a total of eight BF with fume/flame suppressants
distributed at four facilities among the 21 BF total at 11 Integrated
Iron and Steel Manufacturing facilities. Per-unit capital costs for
converting from fume/flame suppressant control to baghouses are
estimated to be $18 million with $2.7 million in annual unit costs,
where some facilities have two or three units. Total industry costs are
estimated to be $140 million in capital costs and $22 million annual
costs. The estimated cost effectiveness of upgrading the fume/flame
suppressant control to ventilation and baghouses at all eight BF is $7
million/ton of metal HAP with 3 tons of HAP removed, and $160,000/ton
PM with 120 tons of PM removed. We conclude these controls for PM and
metal HAP emissions are not cost effective. Details of this cost
estimate and other aspects of upgrading fume/flame suppressants to
baghouses can be found in the technical memorandum cited above. We ask
for comments and additional information regarding the estimated costs
of these conversions, the underlying assumptions of our analysis, and
our proposed conclusion that converting from the use of fume
suppressant to installation of new baghouses for these sources would
not be cost effective.
b. Process Modifications To Control Dioxins at Sinter Plants
    There are three facilities in the Integrated Iron and Steel
Manufacturing source category that have sinter plants. The sinter
plants are currently regulated by PM and opacity limits on the windbox
exhaust stream, sinter cooler, and discharge end of sinter plant. In
addition, the sinter plant windbox is regulated for organic HAP with
compliance demonstrated by either meeting a VOC limit or a limit on oil
content of the sinter feed. Dioxins/furans are components of the
organic HAP but because of the high toxicity of this HAP, often are
addressed separately under control scenarios. Therefore, our technology
review included exploration of potential control measures that could
further reduce dioxin/furans from sinter plants.
    We conducted a literature search and reviewed various technical
publications (largely from Europe and other countries in the Stockholm
Convention) \27\ regarding potential control technologies and practices
to reduce dioxins from sinter plants and found a number of potential
options that could potentially be applied at sinter plants in the
U.S.28 29 30 These options include urea injection to inhibit
dioxin formation; partial windbox exhaust gas recirculation; post-
exhaust windbox chemical spray (monoethanolamine and triethanolamine
dissolved in water and sprayed onto exhaust); and elimination of
certain inputs (e.g., no ESP dust). The European Union also included
these measures in their 2013 Best Available Technology evaluation.\31\
As far as we know, none of these technologies or practices are
currently used at sinter plants in the U.S. However, based on the
literature cited above, we believe some of these technologies or
measures may be used to control dioxins/furans in other countries (such
as in Europe and other countries complying with the Stockholm
Convention).\27\ Nevertheless, we have not been able to estimate the
costs or effectiveness of these control methods due to lack of cost
information in the literature, nor have we been able to estimate the
feasibility for U.S. facilities. See the technical memorandum cited
above for details on the technology review for dioxin/furans from
sinter plants. We ask for comments on these potential process
modifications and feasibility for control of dioxin/furans from sinter
plants at U.S. Integrated Iron and Steel Manufacturing facilities.
---------------------------------------------------------------------------

    \27\ Stockholm Convention on Persistent Organic Pollutants
(Pops), Texts and Annexes. Revised in 2017. Published by the
Secretariat of the Stockholm Convention, Geneva, Switzerland. May
2018. Available at: http://www.pops.int.
    \28\ Ooi, T. C. and L. Lu. Formation and mitigation of PCDD/Fs
in iron ore sintering. Chemosphere 85 291-299. 2011.
    \29\ Boscolo, M, E., Padoano, and S. Tommasi. Identification of
possible dioxin emission reduction strategies in preexisting iron
ore sinter plants. Institute of Materials, Minerals and Mining.
Published by Maney on behalf of the Institute. Ironmaking and
Steelmaking. 15:35:11.The Charlesworth Group, Wakefield, UK. October
19, 2007.
    \30\ Lanzerstorfer, C. State of the Art in Air Pollution Control
for Sinter Plants. Chapter 18, in Ironmaking and Steelmaking
Processes. P. Cavaliere, Ed. Springer International Publishing,
Springer Nature, Switzerland AG. 2016.
    \31\ Best Available Techniques (BAT) Reference Document for Iron
and Steel Production. Industrial Emissions Directive 2010/75/EU
(Integrated Pollution Prevention and Control). R. Remus, M. A.
Aguado-Monsonet. S. Roudier, L. D. Sancho. European Commission,
Joint Research Centre, Institute for prospective technological
studies. European IPPC Bureau, Seville, Spain. Luxembourg
Publications Office of the European Union. doi:10.2791/97469. 2013.
---------------------------------------------------------------------------

c. Technology Review of Point Sources
    Considering all the information described above in our technology
reviews, we have not identified any developments in practices,
processes, or technologies that warrant revision of the NESHAP for
point sources. Therefore, we are not proposing any changes to the
NESHAP pursuant to section 112(d)(6) of the CAA for point sources.
    Other than the technologies and measures described above, we have
not identified any additional potential developments in practices,
processes, or technologies available to control emissions from point
sources. Based on consideration of all the information described above,
we are proposing that no additional standards are necessary under
section 112(d)(6) of the CAA. We solicit comments on this proposed
decision.
2. What are the results of our technology review for nonpoint sources?
    Fugitive emissions generated within the BF casthouse and BOPF shop
from activities such as charging, tapping, and door openings for
maintenance and process monitoring are partially controlled by
secondary capture systems that route emissions captured by hoods and
other collection systems to control devices that are either the primary
control system or stand-alone secondary control devices. Because
capture of fugitive emissions within the BF casthouse and BOPF shop is
not always done or complete (i.e., not 100 percent) some uncaptured
fugitive emissions escape through roof vents and other openings. To
restrict the amount of fugitive emissions that escape the BF casthouse
and BOPF shop, the NESHAP set opacity limits of 20 percent (3-minute
average) for all openings at existing units to be measured a

minimum of once every 5 years (see 40 CFR 63.7821).\32\
---------------------------------------------------------------------------

    \32\ New BOPF sources have a 10-percent opacity limit, with one
6-minute period greater than 10 percent but less than the 20 percent
allowed each steel production cycle. For new BF, the opacity limit
is 15 percent.
---------------------------------------------------------------------------

    In the analyses for nonpoint sources (described in sections II,
III, and IV.B), we estimated the amount of fugitive PM and metal HAP
potentially emitted from these two nonpoint sources, BF casthouses and
BOPF shops. The occurrence of visible plumes of fugitives being emitted
from these process structures has been observed during inspections and
documented in reports and photographs by EPA Regional staff for years
2008 to present.\2\ In the ample margin of safety analysis under Option
1 described above (see section IV.B), we evaluated potential work
practices to reduce uncaptured fugitive emissions from BF casthouses
and BOPF shops; these sources contribute the highest risk of all UFIP
sources. We also considered whether these work practices (described
above under Option 1 in section IV.B to reduce fugitive emissions and
associated risks from these sources) may constitute a development in
work practices, processes, or technology to reduce fugitive emissions
from BF casthouses and BOPF shops pursuant to section 112(d)(6) of the
CAA that was not identified or considered during development of the
original MACT standards. For more details of the technology review, see
the technical memorandum titled Technology Review for the Integrated
Iron and Steel NESHAP, available in the docket to this rule for details
of the evaluation of work practices for control of fugitive HAP
emissions from BF casthouses and BOPF shops. The estimated capital
costs for work practices for these two nonpoint sources are $1.4
million and annualized costs are $1.7 million. We estimate these work
practices would achieve about 173 tpy reduction in metal HAP.
    Nevertheless, as described above, there are significant
uncertainties in the baseline UFIP emissions, estimated reductions that
would be achieved by the work practices, and costs. There are also
uncertainties regarding the effect the work practices would have on
facility operations, economics, and safety.
    After considering all the information described above, we propose
to find that there are no developments in practices, processes, or
control technologies that necessitate revising the standards for these
two UFIP sources under CAA section 112(d)(6). This decision is based
largely on the considerable uncertainties described above along with
the cost issues.
    We ask for comments on our proposed decision, the costs and
effectiveness of the work practices for the two UFIP sources, and
whether these work practices should be viewed as a development in
practices, processes, or technologies (pursuant to CAA section
112(d)(6)) to reduce emissions at BF casthouses and BOPF shops, and
whether further control of the above-mentioned fugitives from these
processes by implementation of the work practices should be required
under the technology review for this source category. These costs and
reductions are described in detail in the technical memorandum titled
Cost Estimates and Other Impacts for the Integrated Iron and Steel Risk
and Technology Review, available in the docket to this rule, and
discussed above.
    In summary, we propose to find that there are no cost-effective
developments in practices, processes, or control technologies for these
two UFIP sources. Therefore, we are not proposing any requirements
under CAA section 112(d)(6) based on our technology review. However, we
are soliciting comments on the potential of these work practices to
reduce emissions from the two UFIP sources, as described above.

D. What actions are we taking pursuant to CAA sections 112(d)(2) and
112(d)(3)?

    Separate from the RTR, in this action we are proposing standards
for mercury emissions pursuant to CAA section 112(d)(2) and (3).\33\
The results of the analyses performed pursuant to CAA section 112(d)(2)
and (3) and the standards proposed are presented below.
---------------------------------------------------------------------------

    \33\ The EPA has authority under CAA section 112(d)(2) and (3)
to set MACT standards for previously unregulated emission points.
The EPA also retains the discretion to revise a MACT standard under
the authority of CAA section 112(d)(2) and (3) (see Portland Cement
Ass'n v. EPA, 665 F.3d 177, 189 (D.C. Cir. 2011), such as when it
identifies an error in the original standard. See also Medical Waste
Institute v. EPA, 645 F. 3d 420, 426 (D.C. Cir. 2011) (upholding EPA
action establishing MACT floors, based on post-compliance data, when
originally-established floors were improperly established).
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1. Background Regarding Mercury Emissions From the Source Category
    The current NESHAP for Integrated Iron and Steel Manufacturing does
not include mercury emission standards. Based on data from the 2010
ICR, we estimate the facilities in the source category emitted about
1,000 lb/year of mercury in 2010. Based on the CAA section 114 test
results, most (80 percent) of the mercury is from the BOPF and
associated operations (i.e., HMTDS and ladle metallurgy). An
examination of possible sources of mercury from the BOPF and associated
operations revealed that the use of post-consumer steel scrap, as
reported in the ICR, was the most likely source of mercury. Based on
our understanding of the types of scrap and raw materials processed and
the likely sources of mercury in various materials, we conclude that
the predominant contributor to mercury emissions at integrated iron and
steel facilities is the motor vehicle convenience switches that contain
mercury (i.e., mercury switches) that are found in vehicles built
before 2003 and end up in steel scrap. Therefore, it is reasonable to
conclude that mercury emissions from Integrated Iron and Steel
Manufacturing facilities predominantly result from steel scrap
containing mercury switches fed into the BOPF. Details of the sources
of mercury emissions can be found in the technical memorandum titled
Mercury Emissions, Controls, and Costs at Integrated Iron and Steel
Facilities, available in the docket to this rule, that describes the
sources of mercury from Integrated Iron and Steel Manufacturing
facilities and the issues and costs involved in control of mercury.
    However, based on models developed from analysis of the age of
motor vehicles in the U.S. vehicle fleet, we estimate that mercury
emissions from this source category are about 50 percent lower today as
compared to 2010 and are expected to continue to decline over the
coming years due to the 2003 U.S. motor vehicle mercury switch ban and
the National Vehicle Mercury Switch Recovery Program (NVMSRP). For more
information about the mercury emissions and predicted reductions see
the technical memorandum titled Mercury Emissions, Controls, and Costs
at Integrated Iron and Steel Facilities, available in the docket for
this action.
    The NVMSRP is a cooperative effort established in 2006 among
vehicle manufacturers, steel manufacturers, vehicle dismantlers, scrap
shredders, the EPA, and other stakeholders, to support the removal of
mercury switches from end-of-life vehicles. The NVMSRP involves more
than 10,000 steel recyclers. The initial Memorandum of Understanding
(MOU) between the NVMSRP parties was signed in 2006. On November 15,
2018, the EPA signed a renewed MOU that extends the program through
2021. Given its success, the EPA continues to support the NVMSRP that
already has removed and safely recycled more than 6.8

million mercury switches containing a total of more than 7.6 tons of
mercury. The MOU, renewed MOU, and other information regarding the
NVMSRP are available at: https://www.epa.gov/smartsectors/mercury-switch-recovery-program, and in the docket for this rule.
2. Reconsideration Petition
    In 2004, the EPA received a petition for reconsideration from the
Sierra Club, who referred to the EPA's statement in the Integrated Iron
and Steel Manufacturing NESHAP that steel plants emit mercury but not
in appreciable quantities. Sierra Club argued that the CAA does not
allow the EPA not to set standards because emissions are insignificant.
In 2005, the EPA granted reconsideration to evaluate a possible mercury
standard. Consequently, the EPA is proposing in this action an
emissions standard for mercury for the Integrated Iron and Steel
Manufacturing source category pursuant to CAA section 112(d)(3).
3. Proposed MACT Standards for Mercury
    Section 302(k) of the CAA defines an emission standard as a
requirement ``which limits the quantity, rate, or concentration of
emissions of air pollutants on a continuous basis, including any
requirement relating to the operation or maintenance of a source to
assure continuous emission reduction, and any design, equipment, work
practice or operational standard promulgated under this chapter.''
    Pursuant to CAA section 112(d)(3), we are proposing a MACT floor
limit of 0.00026 lbs of mercury per ton of scrap processed as an input-
based limit for all existing BOPFs and existing integrated iron and
steel manufacturing facilities. This limit was derived using ICR test
data of the mass of mercury emissions from all BOPFs and related units
(HMTDS and ladles) at each facility per mass of scrap used by each
facility in their BOPFs with the assumption that the mass of mercury
emitted from all BOPFs and related units is equivalent to the mass of
mercury in the scrap input because mercury is neither created or
destroyed in the BOPF. The mercury-to-scrap input ratios from the best
performing five facilities out of all 11 integrated iron and steel
manufacturing facilities in the Integrated Iron and Steel Manufacturing
source category were used to develop an input-based MACT floor for
mercury. We then determined an upper prediction limit (UPL) to develop
the mercury standard that incorporates the potential variability in
future measurements. Because there are fewer than 30 sources in the
Integrated Iron and Steel Manufacturing source category, as described
below, we evaluated the best performing five sources in the category,
pursuant to CAA section 112(d)(3)(B).
    The EPA's MACT analyses use the UPL approach to identify the
average emission limitation achieved by the best performing sources.
The EPA uses this approach because it incorporates the average
performance of the best performing sources as well as the variability
of the performance during testing conditions. The UPL represents the
value which one can expect the mean of a specified number of future
observations (e.g., 3-run average) to fall below for the specified
level of confidence (99 percent), based upon the results from the same
population. In other words, the UPL estimates what the upper bound of
future values will be based upon present or past background data. The
UPL approach encompasses all the data point-to-data point variability
in the collected data, as derived from the dataset to which it is
applied. For more details regarding how this limit was derived, see the
technical memorandum titled Mercury Emissions, Controls, and Costs at
Integrated Iron and Steel Facilities, located in the docket for this
rule, and described above.
    We are proposing that existing facilities would have two options to
demonstrate compliance with the proposed input-based limit of 0.00026
lbs of mercury per ton of scrap processed, as follows: (1) Conduct an
annual emissions test at all BOPF-related units and convert the sum of
the results to input-based units (i.e., lb of mercury per ton of scrap
input) and document the results in a test report that can be submitted
electronically to the delegated authority with the results (see section
IV.E below); or (2) certify annually that the facility obtains all of
their scrap from NVMSRP participants (or similar program as approved by
the delegated authority) or establish that their scrap is not likely to
contain mercury.
    Although we do not know exactly what type of scrap was used when
the integrated iron and steel facilities performed the ICR testing for
mercury,\34\ we assume the scrap was either NVMSRP scrap or scrap with
higher amounts of mercury per ton of scrap than NVMSRP scrap. It is
reasonable for the EPA to conclude that NVMSRP scrap in the future will
contain similar levels of mercury or less mercury than the scrap used
to develop the MACT floor limit, and this proposal relies on that
conclusion. Therefore, if a facility opts to comply with the emission
limit by certifying that all their scrap is from NVMSRP participants
(or a similar approved program) or establishes that their scrap is not
likely to contain mercury, it is also reasonable to conclude that the
amount of mercury in the scrap achieves the same level of mercury
reduction or more reduction as the numeric MACT floor limit.
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    \34\ It is our understanding that there are at least three
facilities in the Integrated Iron and Steel Manufacturing source
category that obtain all their steel scrap from scrap providers that
participate in the NVMSRP. (Personal communication (telephone).) P.
Balserak, AISI, Washington, DC, with C. French, U. S. EPA, Research
Triangle Park, North Carolina. December 13, 2018.). Also, during
other discussions in 2018, industry representatives indicated they
believed all, or most, facilities obtain all of their steel scrap
from scrap providers that participate in the NVMSRP. However, we
have not yet confirmed this information.
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    Pursuant to CAA section 112(d)(3) requirements for new sources, the
standard for new sources shall not be less stringent than the emission
control that is achieved in practice by the best controlled similar
source, we are proposing a new source MACT limit of 0.00008 lbs of
mercury per ton of scrap processed as an input-based limit for any new
BOPF and new integrated iron and steel manufacturing facility. A new
BOPF and new integrated iron and steel manufacturing facility is
defined to be any BOPF or facility constructed or reconstructed on or
after August 16, 2019. This limit was derived using ICR test data of
the mass of mercury emissions from all BOPF and related units (HMTDS
and ladles) per mass of scrap used by the lowest-emitting facility. In
addition, similar to existing sources above, we are proposing that new
BOPF or new facilities would have two options to demonstrate compliance
with the proposed input-based limit of 0.00008 lbs of mercury per ton
of scrap processed, as follows: (1) Conduct an annual emissions test at
all BOPF-related units and convert the sum of the results to input-
based units (i.e., lbs of mercury per ton of scrap input) and document
the results in a test report that can be submitted electronically to
the delegated authority with the results (see section IV.E below); or
(2) certify annually that the facility obtains all of their scrap from
NVMSRP participants (or similar program as approved by the delegated
authority) or certify that their scrap is not likely to contain
mercury.
    Following the same reasoning discussed above in connection with the
existing source standard, although we do not know exactly what type of
scrap was used when the integrated iron and steel facilities performed
the ICR testing

for mercury, we assume the scrap was either NVMSRP scrap or scrap with
higher amounts of mercury per ton of scrap than NVMSRP scrap.
Therefore, it is reasonable for the EPA to conclude that scrap subject
to the NVMSRP or other approved scrap program in the future will
contain similar levels of mercury or less mercury than the scrap used
to develop the MACT floor limit, and this proposal relies on that
conclusion. We request comment on our proposed emissions standards for
mercury at new and existing BOPF-related units.
    In terms of cost impacts, our analysis indicates that all
facilities could meet the mercury limit in 2020 without any additional
add-on controls. With declining mercury levels in vehicle scrap, we
expect that all facilities that obtain all their scrap from suppliers
who participate in the NVMSRP or similar approved program will meet
this input-based standard without the need for any additional controls.
For facilities that choose to comply by certifying they get all their
scrap from NVMSRP participants, or a similar switch removal program, we
estimate that the only costs to comply with this standard would be for
recordkeeping and reporting, which we estimate at $1,058 per year per
facility, and $11,639 per year for all 11 integrated iron and steel
manufacturing facilities. If one or more facilities choose to conduct
annual emissions tests, their costs would be higher due to the costs
for the emissions tests. The costs to conduct an annual emissions test
at all BOPF-related units, convert the sum of the results to input-
based units (i.e., lb of mercury per ton of scrap input), and document
the results in a test report that can be submitted electronically to
the delegated authority with the results is estimated to be
approximately $151,000 per year per facility and $1,660,000 for the
total industry.
    However, we assume all, or most, facilities will choose the option
to comply by certifying scrap selection. We request comment on these
compliance costs and also the assumption that purchasing scrap from
NVMSRP scrap providers or a similar approved program results in a small
additional cost to facilities. For more information regarding the
derivation of the cost estimates for this proposed mercury standard and
all aspects of mercury emissions and controls, see the document titled
Mercury Emissions, Controls, and Costs at Integrated Iron and Steel
Facilities, available in the docket to this rule.
4. Consideration of Beyond-the-Floor Options
    The EPA also evaluated possible beyond-the-floor options based on
the addition of ACI with baghouses on BOPF and related units to further
reduce emissions of mercury coming from their existing control devices
(scrubbers, baghouses, and ESPs). We estimate the total capital costs
for installing baghouse (if not already present) and ACI systems would
be $24 million and annualized costs would be $38 million, and would
achieve about 280 lbs mercury reduction per year for the first few
years of compliance with such standards, based on the amount of mercury
projected to be in the scrap in 2020 and considering the decrease in
mercury expected in motor vehicle scrap. This results in estimated cost
effectiveness of $136,000 per lb of mercury reductions. However, under
this option, the amount of emissions and associated reductions would
decrease over time as a result of the expected decline in mercury input
due to the 2003 ban on mercury switches and aging of the vehicle fleet.
Therefore, the beyond-the-floor controls would become less cost
effective over time. For this reason, and because of the relatively
high capital and annualized cost of ACI with baghouses, and poor cost
effectiveness, the EPA is not proposing a beyond-the-floor option based
on ACI with baghouses. See the document titled Mercury Emissions,
Controls, and Costs at Integrated Iron and Steel Facilities, available
in the docket to this rule, for details regarding the derivation of the
cost and emission estimates for the beyond-the-floor option.
5. New Terms and Definitions
    With the addition of proposed MACT standards for mercury and to
clarify a few other aspects of the NESHAP, we are proposing to add new
terms along with their definitions. We ask for comment on the clarity
of these definitions.
     Basic oxygen process furnace group means the collection of
BOPF shop steelmaking operation units including the BOPF primary units
(BOPF emissions from oxygen blow iron refining), BOPF secondary units
(secondary fugitive emissions in the shop from iron charging, tapping,
and auxiliary processes not elsewhere controlled), ladle metallurgy
units, and hot metal transfer, desulfurization, and slag skimming
units;
     Deviation for an affected source subject to this subpart,
or an owner or operator of such a source, also includes failure to meet
any requirement or obligation established by this rule, including, but
not limited to, any emission limitation (including operating limits),
standard, or operation and maintenance requirement;
     Mercury switch means a mercury-containing capsule or
switch assembly that is part of a convenience light switch mechanism
installed in a motor vehicle;
     Motor vehicle means an automotive vehicle not operated on
rails and usually operated with rubber tires for use on highways;
     Motor vehicle scrap means post-consumer scrap from
discarded vehicles or automobile bodies, including automobile body
hulks that have been processed through a shredder. Motor vehicle scrap
does not include automobile manufacturing bundles or miscellaneous
vehicle parts, such as wheels, bumpers, or other components that do not
contain mercury switches. Motor vehicle scrap typically is not sold
separately but is combined with other steel scrap for sale;
     Opening means any roof monitor, vent, door, window, hole,
crack, or other conduit that allows gas to escape to the atmosphere
from a BF casthouse or BOPF shop;
     Post-consumer steel scrap means steel scrap that is
composed of materials made of steel that were purchased by households
or by commercial, industrial, and institutional facilities in their
role as end-users of the product and which can no longer be used for
its intended purpose;
     Pre-consumer steel scrap means steel scrap that is left
over from industrial or manufacturing processes and which is
subsequently recycled as scrap. Other terms used to describe this scrap
are new, home, run-around, prompt-industrial, and return scrap;
     Scrap provider means the company or person (including a
broker) who contracts directly with a steel mill to provide steel
scrap. Scrap processors such as shredder operators or vehicle
dismantlers that do not sell scrap directly to a steel mill are not
scrap providers; and
     Steel scrap means pre-consumer and post-consumer discarded
steel that is processed by scrap providers for resale (post-consumer)
or used on-site (pre-consumer or run-around scrap from within a
facility or company). Post-consumer steel scrap may or may not contain
motor vehicle scrap, depending on the type of scrap. In regard to motor
vehicle scrap, steel scrap only can be classified as ``scrap that is
likely to contain motor vehicle scrap'' vs. ``scrap that is not likely
to contain motor vehicle scrap,'' as determined by the scrap provider.

E. What other actions are we proposing?

    In addition to the proposed actions described above, we are
proposing additional revisions to the NESHAP. We are proposing
revisions to the SSM provisions of the MACT rule in order to ensure
that they are consistent with the Court decision in Sierra Club v. EPA,
551 F. 3d 1019 (D.C. Cir. 2008), which vacated two provisions that
exempted sources from the requirement to comply with otherwise
applicable CAA section 112(d) emission standards during periods of SSM.
We also are proposing various other changes to modify reporting and
monitoring. Our analyses and proposed changes related to these issues
are discussed below.
1. SSM
    In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 (D.C.
Cir. 2008), the Court vacated portions of two provisions in the EPA's
CAA section 112 regulations governing the emissions of HAP during
periods of SSM. Specifically, the Court vacated the SSM exemption
contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), holding that
under section 302(k) of the CAA, CAA section 112 emissions standards or
limitations must be continuous in nature and that the SSM exemption
violates the CAA's requirement that some CAA section 112 standards
apply continuously.
    We are proposing the elimination of the SSM exemption in this rule
which appears at 40 CFR 63.7810(a) and Table 4. Consistent with Sierra
Club v. EPA, we are proposing standards in this rule that apply at all
times. We are also proposing several revisions to Table 4 (the General
Provisions Applicability Table) as is explained in more detail below.
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 and revise certain recordkeeping and
reporting requirements related to the SSM exemption as further
described below.
    The EPA has attempted to ensure that the provisions we are
proposing to eliminate are inappropriate, unnecessary, or redundant in
the absence of the SSM exemption. We are specifically seeking comment
on whether we have successfully done so.
    In proposing the standards in this rule, the EPA has taken into
account startup and shutdown periods and, for the reasons explained
below, has not proposed alternate standards for those periods. The
integrated iron and steel manufacturing industry has not identified
(and there are no data indicating) any specific problems with removing
the SSM provisions. However, we solicit comment on whether any
situations exist where separate standards, such as work practices,
would be more appropriate during periods of startup and shutdown rather
than the current standard.
    Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. Malfunctions,
in contrast, are neither predictable nor routine. Instead they are, by
definition, sudden infrequent and not reasonably preventable failures
of emissions control, process, or monitoring equipment. (40 CFR 63.2)
(definition of malfunction). The EPA interprets CAA section 112 as not
requiring emissions that occur during periods of malfunction to be
factored into development of CAA section 112 standards and this reading
has been upheld as reasonable by the Court in U.S. Sugar Corp. v. EPA,
830 F.3d 579, 606-610 (2016). 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 emission
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 sources when setting emission standards. As the
Court has recognized, the phrase ``average emissions limitation
achieved by the best performing 12 percent of'' sources ``says nothing
about how the performance of the best units is to be calculated.''
Nat'l Ass'n of Clean Water Agencies v. EPA, 734 F.3d 1115, 1141 (D.C.
Cir. 2013). While the EPA accounts for variability in setting emissions
standards, nothing in CAA section 112 requires the Agency to consider
malfunctions as part of that analysis. The EPA is not required to treat
a malfunction in the same manner as the type of variation in
performance that occurs during routine operations of a source. A
malfunction is a failure of the source to perform in a ``normal or
usual manner'' and no statutory language compels the EPA to consider
such events in setting CAA section 112 standards.
    As the Court recognized in U.S. Sugar Corp., accounting for
malfunctions in setting standards 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. Id. at 608 (``the
EPA would have to conceive of a standard that could apply equally to
the wide range of possible boiler malfunctions, ranging from an
explosion to minor mechanical defects. Any possible standard is likely
to be hopelessly generic to govern such a wide array of
circumstances.''). 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 (D.C. Cir. 1999) (``The 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 (D.C. 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, emissions during a malfunction event can be significantly
higher than emissions at any other time of source operation. For
example, if an air pollution control device with 99-percent removal
goes off-line as a result of a malfunction (as might happen if, for
example, the bags in a baghouse catch fire) and the emission unit is a
steady state type unit that would take days to shut down, the source
would go from 99-percent control to zero control until the control
device was repaired. The source's emissions during the malfunction
would be 100 times higher than during normal operations. As such, the
emissions over a 4-day malfunction period would exceed the annual
emissions of the source during normal operations. As this example
illustrates, accounting for malfunctions could lead to standards that
are not reflective of (and significantly less stringent than) levels
that are achieved by a well-performing non-malfunctioning source. It is
reasonable to interpret CAA section 112 to avoid such a result. The
EPA's approach to malfunctions is consistent with CAA section 112 and
is a reasonable interpretation of the statute.

    Although no statutory language compels the EPA to set standards for
malfunctions, the EPA has the discretion to do so where feasible. For
example, when the EPA conducted the Petroleum Refinery Sector RTR, the
EPA established a work practice standard for unique types of
malfunctions that result in releases from pressure relief devices or
emergency flaring events because the EPA had information to determine
that such work practices reflected the level of control that applies to
the best performers. 80 FR 75178, 75211-14 (December. 1, 2015). The EPA
will consider whether circumstances warrant setting standards for a
particular type of malfunction and, if so, whether the EPA has
sufficient information to identify the relevant best performing sources
and establish a standard for such malfunctions. We also encourage
commenters to provide any such information.
    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).
    If the EPA determines in a particular case that an enforcement
action against a source for violation of an emission standard is
warranted, the source can raise any and all defenses in that
enforcement action and the Federal district court will determine what,
if any, relief is appropriate. The same is true for citizen enforcement
actions. Similarly, the presiding officer in an administrative
proceeding can consider any defense raised and determine whether
administrative penalties are appropriate.
    In summary, the EPA interpretation of the CAA and, in particular,
CAA section 112 is reasonable and encourages practices that will avoid
malfunctions. Administrative and judicial procedures for addressing
exceedances of the standards fully recognize that violations may occur
despite good faith efforts to comply and can accommodate those
situations. U.S. Sugar Corp. v. EPA, 830 F.3d 579, 606-610 (2016).
a. 40 CFR 63.7810(c) General Duty
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.6(e)(1)(i) and including a ``no'' in
column 3. Section 63.6(e)(1)(i) describes the general duty to minimize
emissions. Some of the language in that section is no longer necessary
or appropriate in light of the elimination of the SSM exemption. We are
proposing instead to add general duty regulatory text at 40 CFR
63.7810(c) that reflects the general duty to minimize emissions while
eliminating the reference to periods covered by an SSM exemption. The
current language in 40 CFR 63.6(e)(1)(i) characterizes what the general
duty entails during periods of SSM. With the elimination of the SSM
exemption, there is no need to differentiate between normal operations,
startup and shutdown, and malfunction events in describing the general
duty. Therefore, the language the EPA is proposing for 40 CFR
63.7810(c) does not include that language from 40 CFR 63.6(e)(1).
    We are also proposing to revise the General Provisions table (Table
4) by adding an entry for 40 CFR 63.6(e)(1)(ii) and including a ``no''
in column 3. Section 63.6(e)(1)(ii) imposes requirements that are not
necessary with the elimination of the SSM exemption or are redundant
with the general duty requirement being added at 40 CFR 63.7810(c).
b. SSM Plan
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.6(e)(3) and including a ``no'' in
column 3. Generally, the paragraphs under 40 CFR 63.6(e)(3) require
development of an SSM plan and specify SSM recordkeeping and reporting
requirements related to the SSM plan. As noted, the EPA is proposing to
remove the SSM exemptions. Therefore, affected units will be subject to
an emission standard during such events. The applicability of a
standard during such events will ensure that sources have ample
incentive to plan for and achieve compliance and, thus, the SSM plan
requirements are no longer necessary.
c. Compliance With Standards
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.6(f)(1) and including a ``no'' in
column 3. The current language of 40 CFR 63.6(f)(1) exempts sources
from non-opacity standards during periods of SSM. As discussed above,
the Court in Sierra Club vacated the exemptions contained in this
provision and held that the CAA requires that some CAA section 112
standards apply continuously. Consistent with Sierra Club, the EPA is
proposing to revise standards in this rule to apply at all times.
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.6(h)(1) and including a ``no'' in
column 3. The current language of 40 CFR 63.6(h)(1) exempts sources
from opacity standards during periods of SSM. As discussed above, the
Court in Sierra Club vacated the exemptions contained in this provision
and held that the CAA requires that some CAA section 112 standards
apply continuously. Consistent with Sierra Club, the EPA is proposing
to revise standards in this rule to apply at all times.
d. 40 CFR 63.7822 and 63.7823 Performance Testing
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.7(e)(1) and including a ``no'' in
column 3. Section 63.7(e)(1) describes performance testing
requirements. The EPA is instead proposing to add a performance testing
requirement at 40 CFR 63.7822(a) and 63.7823(a). The performance
testing requirements we are proposing to add differ from the General
Provisions performance testing provisions in several respects. The
regulatory text does not include the language in 40 CFR 63.7(e)(1) that
restated the SSM exemption and language that precluded startup and
shutdown periods from being considered ``representative'' for purposes
of performance testing. The revised performance testing provisions
require testing under representative operating conditions and exclude
periods of startup and shutdown.
    As in 40 CFR 63.7(e)(1), performance tests conducted under this
subpart should not be conducted during malfunctions because conditions
during malfunctions are often not representative of normal operating
conditions. The EPA is proposing to add language that requires the
owner or operator to record the process information that is necessary
to document operating conditions during the test and include in such
record an explanation to support that such conditions represent normal
operation. Section 63.7(e) requires that the owner or operator make
available to the Administrator such records ``as may be necessary to
determine the condition of the performance test'' available to the
Administrator upon request but does not specifically require the
information

to be recorded. The regulatory text the EPA is proposing to add to this
provision builds on that requirement and makes explicit the requirement
to record the information.
e. Monitoring
    We are proposing to revise the General Provisions table (Table 4)
by adding entries for 40 CFR 63.8(c)(1)(i) and (iii) and including a
``no'' in column 3. The cross-references to the general duty and SSM
plan requirements in those subparagraphs are not necessary in light of
other requirements of 40 CFR 63.8 that require good air pollution
control practices (40 CFR 63.8(c)(1)) and that set out the requirements
of a quality control program for monitoring equipment (40 CFR 63.8(d)).
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.8(d)(3) and including a ``no'' in
column 3. The final sentence in 40 CFR 63.8(d)(3) refers to the General
Provisions' SSM plan requirement which is no longer applicable. The EPA
is proposing to add to the rule at 40 CFR 63.7842(b)(3) text that is
identical to 40 CFR 63.8(d)(3) except that the final sentence is
replaced with the following sentence: ``The program of corrective
action should be included in the plan required under Sec.
63.8(d)(2).''
f. 40 CFR 63.7842 Recordkeeping
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(b)(2)(i) and including a ``no'' in
column 3. Section 63.10(b)(2)(i) describes the recordkeeping
requirements during startup and shutdown. These recording provisions
are no longer necessary because the EPA is proposing that recordkeeping
and reporting applicable to normal operations would apply to startup
and shutdown. In the absence of special provisions applicable to
startup and shutdown, such as a startup and shutdown plan, there is no
reason to retain additional recordkeeping for startup and shutdown
periods.
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(b)(2)(ii) and including a ``no'' in
column 3. Section 63.10(b)(2)(ii) describes the recordkeeping
requirements during a malfunction. The EPA is proposing to add such
requirements to 40 CFR 63.7842. The regulatory text we are proposing to
add differs from the General Provisions it is replacing in that the
General Provisions requires the creation and retention of a record of
the occurrence and duration of each malfunction of process, air
pollution control, and monitoring equipment. The EPA is proposing that
this requirement apply to any failure to meet an applicable standard
and is requiring that the source record the date, time, and duration of
the failure rather than the ``occurrence.'' The EPA is also proposing
to add to 40 CFR 63.7842(a)(4) a requirement that sources keep records
that include a list of the affected source or equipment and actions
taken to minimize emissions, an estimate of the quantity of each
regulated pollutant emitted over the standard for which the source
failed to meet the standard, and a description of the method used to
estimate the emissions. Examples of such methods would include product-
loss calculations, mass balance calculations, measurements when
available, or engineering judgment based on known process parameters.
The EPA is proposing to require that sources keep records of this
information to ensure that there is adequate information to allow the
EPA to determine the severity of any failure to meet a standard, and to
provide data that may document how the source met the general duty to
minimize emissions when the source has failed to meet an applicable
standard.
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(b)(2)(iv) and including a ``no'' in
column 3. When applicable, the provision requires sources to record
actions taken during SSM events when actions were inconsistent with
their SSM plan. The requirement is no longer appropriate because SSM
plans would no longer be required. The requirement previously
applicable under 40 CFR 63.10(b)(2)(iv)(B) to record actions to
minimize emissions and record corrective actions is now applicable by
reference to 40 CFR 63.7842(a)(5).
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(b)(2)(v) and including a ``no'' in
column 3. When applicable, the provision requires sources to record
actions taken during SSM events to show that actions taken were
consistent with their SSM plan. The requirement is no longer
appropriate because SSM plans would no longer be required.
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(c)(15) and including a ``no'' in
column 3. The EPA is proposing that 40 CFR 63.10(c)(15) no longer
apply. When applicable, the provision allows an owner or operator to
use the affected source's SSM plan or records kept to satisfy the
recordkeeping requirements of the SSM plan, specified in 40 CFR
63.6(e), to also satisfy the requirements of 40 CFR 63.10(c)(10)
through (12). The EPA is proposing to eliminate this requirement
because SSM plans would no longer be required, and, therefore, 40 CFR
63.10(c)(15) no longer serves any useful purpose for affected units.
g. 40 CFR 63.7841 Reporting
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(d)(5)(i) and including a ``no'' in
column 3. Section 63.10(d)(5)(i) describes the reporting requirements
for startups, shutdowns, and malfunctions. To replace the General
Provisions reporting requirement, the EPA is proposing to add reporting
requirements to 40 CFR 63.7841(b)(4). The replacement language differs
from the General Provisions requirement in that it eliminates periodic
SSM reports as a stand-alone report. We are proposing language that
requires sources that fail to meet an applicable standard at any time
to report the information concerning such events in the semiannual
reporting period compliance report already required under this rule. We
are proposing that the report would contain the number, date, time,
duration, and the cause of such events (including unknown cause, if
applicable), a list of the affected source or equipment, an estimate of
the quantity of each regulated pollutant emitted over any emission
limit, and a description of the method used to estimate the emissions.
    Examples of such methods would include product-loss calculations,
mass balance calculations, measurements when available, or engineering
judgment based on known process parameters. The EPA is proposing this
requirement to ensure that there is adequate information to determine
compliance, to allow the EPA to determine the severity of the failure
to meet an applicable standard, and to provide data that may document
how the source met the general duty to minimize emissions during a
failure to meet an applicable standard.
    We would no longer require owners or operators to determine whether
actions taken to correct a malfunction are consistent with an SSM plan,
because plans would no longer be required. The proposed amendments,
therefore, eliminate the cross reference to 40 CFR 63.10(d)(5)(i) that
contains the description of the previously required SSM report format
and submittal schedule from this section. These specifications are no
longer

necessary because the events would be reported in otherwise required
reports with similar format and submittal requirements.
    We are proposing to revise the General Provisions table (Table 4)
by adding an entry for 40 CFR 63.10(d)(5)(ii) and including a ``no'' in
column 3. Section 63.10(d)(5)(ii) describes an immediate report for
startups, shutdown, and malfunctions when a source failed to meet an
applicable standard but did not follow the SSM plan. We would no longer
require owners and operators to report when actions taken during a
startup, shutdown, or malfunction were not consistent with an SSM plan,
because plans would no longer be required.
2. Electronic Reporting
    Through this proposal, the EPA is proposing that owners and
operators of integrated iron and steel manufacturing facilities submit
the required electronic copies of summaries of performance test results
and semiannual reports through the EPA's Central Data Exchange (CDX)
using the Compliance and Emissions Data Reporting Interface (CEDRI). A
description of the electronic data submission process is provided in
the memorandum, Electronic Reporting Requirements for New Source
Performance Standards (NSPS) and National Emission Standards for
Hazardous Air Pollutants (NESHAP) Rules, available in Docket ID No.
EPA-HQ-OAR-2002-0083. The proposed rule requires that performance test
results collected using test methods that are supported by the EPA's
Electronic Reporting Tool (ERT), as listed on the ERT website \35\ at
the time of the test, be submitted in the format generated through the
use of the ERT, and that other performance test results be submitted in
portable document format (PDF) using the attachment module of the ERT.
Similarly, performance evaluation results of continuous monitoring
systems measuring relative accuracy test audit pollutants that are
supported by the ERT at the time of the test would be submitted in the
format generated through the use of the ERT and other performance
evaluation results be submitted in PDF using the attachment module of
the ERT.
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    \35\ https://www.epa.gov/electronic-reporting-air-emissions/electronic-reporting-tool-ert.
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    For semiannual compliance reports, the proposed rule requires that
owners and operators use the appropriate spreadsheet template to submit
information to CEDRI. A draft version of the proposed template for
these reports is included in the docket for this rulemaking.\36\ The
EPA specifically requests comment on the content, layout, and overall
design of the template.
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    \36\ See 40 CFR part 63, subpart FFFFF, National Emission
Standards for Hazardous Air Pollutants: Integrated Iron and Steel
Manufacturing Facilities--40 CFR 63.7841(b), Semiannual Compliance
Report Spreadsheet Template, available at Docket ID. No. EPA-HQ-OAR-
2002-0083.
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    Additionally, the EPA has identified two broad circumstances in
which electronic reporting extensions may be provided. In both
circumstances, the decision to accept the claim of needing additional
time to report is within the discretion of the Administrator, and
reporting should occur as soon as possible. The EPA is providing these
potential extensions to protect owners and operators from noncompliance
in cases where they cannot successfully submit a report by the
reporting deadline for reasons outside of their control. The situation
where an extension may be warranted due to outages of the EPA's CDX or
CEDRI which precludes an owner or operator from accessing the system
and submitting required reports is addressed in 40 CFR 63.7841(e). The
situation where an extension may be warranted due to a force majeure
event, which is defined as an event that would be or has been caused by
circumstances beyond the control of the affected facility, its
contractors, or any entity controlled by the affected facility that
prevents an owner or operator from complying with the requirement to
submit a report electronically as required by this rule is addressed in
40 CFR 63.7841(f). Examples of such events are acts of nature, acts of
war or terrorism, or equipment failure or safety hazards beyond the
control of the facility.
    The electronic submittal of the reports addressed in this proposed
rulemaking will increase the usefulness of the data contained in those
reports, is in keeping with current trends in data availability and
transparency, will further assist in the protection of public health
and the environment, will improve compliance by facilitating the
ability of regulated facilities to demonstrate compliance with
requirements, and by facilitating the ability of delegated state,
local, tribal, and territorial air agencies and the EPA to assess and
determine compliance, and will ultimately reduce burden on regulated
facilities, delegated air agencies, and the EPA. Electronic reporting
also eliminates paper-based, manual processes, thereby saving time and
resources, simplifying data entry, eliminating redundancies, minimizing
data reporting errors, and providing data quickly and accurately to the
affected facilities, air agencies, the EPA, and the public. Moreover,
electronic reporting is consistent with the EPA's plan \37\ to
implement Executive Order 13563 and is in keeping with the EPA's
Agency-wide policy \38\ developed in response to the White House's
Digital Government Strategy.\39\ For more information on the benefits
of electronic reporting, see the memorandum titled Electronic Reporting
Requirements for New Source Performance Standards (NSPS) and National
Emission Standards for Hazardous Air Pollutants (NESHAP) Rules,
available in Docket ID No. EPA-HQ-OAR-2002-0083.
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    \37\ EPA's Final Plan for Periodic Retrospective Reviews, August
2011. Available at: https://www.regulations.gov/document?D=EPA-HQ-OA-2011-0156-0154.
    \38\ E-Reporting Policy Statement for EPA Regulations, September
2013. Available at: https://www.epa.gov/sites/production/files/2016-03/documents/epa-ereporting-policy-statement-2013-09-30.pdf.
    \39\ Digital Government: Building a 21st Century Platform to
Better Serve the American People, May 2012. Available at: https://obamawhitehouse.archives.gov/sites/default/files/omb/egov/digital-government/digital-government.html.
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3. Incorporation by Reference Under 1 CFR Part 51
    The EPA is proposing regulatory text that includes incorporation by
reference (IBR). In accordance with requirements of 1 CFR 51.5, the EPA
is proposing to incorporate by reference the following documents
described in the amendments to 40 CFR 63.14:
     ANSI/ASME PTC 19.10-1981, Flue and Exhaust Gas Analyses
[Part 10, Instruments and Apparatus], (Issued August 31, 1981), IBR
approved for 40 CFR 63.7822(b) and 63.7824(e). This method determines
quantitatively the gaseous constituents of exhausts resulting from
stationary combustion sources. The gases covered in the method are
oxygen, carbon dioxide, carbon monoxide, nitrogen, sulfur dioxide,
sulfur trioxide, nitric oxide, nitrogen dioxide, hydrogen sulfide, and
hydrocarbons.
     EPA-454/R-98-015, Office of Air Quality Planning and
Standards (OAQPS), Fabric Filter Bag Leak Detection Guidance, September
1997, IBR approved for 40 CFR 63.7831(f). This document provides
guidance on the use of triboelectric monitors as fabric filter bag leak
detectors. The document includes fabric filter and monitoring system
descriptions; guidance on monitor selection, installation, setup,
adjustment, and operation; and quality assurance procedures.
    The EPA has made, and will continue to make, the EPA document
generally

available electronically through https://www.regulations.gov/ and at
the EPA Docket Center (see the ADDRESSES section of this preamble for
more information). The ANSI/ASME document is available from the
American Society of Mechanical Engineers (ASME) at http://www.asme.org;
by mail at Three Park Avenue, New York, NY 10016-5990; or by telephone
at<PHONE_NUMBER>.
4. Technical and Editorial Changes
    The following lists additional proposed changes that address
technical and editorial corrections:
     Revised 40 CFR 63.7822 and 63.7823 to specify the
conditions for conducting performance tests;
     Revised 40 CFR 63.7822, 63.7823, 63.7824, and 63.7833 to
clarify the location in 40 CFR part 60 of applicable EPA test methods;
     Revised 40 CFR 63.7822 and 63.7824 to add IBR for ANSI/
ASME PTC 19.10-1981;
     Revised Tables 1 and 3 to clarify that opacity
observations be made at all openings to the BF casthouse;
     Revised Tables 1, 2, and 3 to clarify that the affected
source is each BOPF shop, rather than only the roof monitor at the BOPF
shop;
     Revised Table 1 to add a mercury emission limit, revised
Table 2 to add demonstration of initial compliance with the mercury
emission limit, and revised Table 3 to add demonstration of continuous
compliance with the mercury emission limit
     Revised 40 CFR 63.7831 to add IBR for EPA-454/R-98-015;
     Revised 40 CFR 63.7835, 63.7841, and 63.7842 to include
the requirements to record and report information on failures to meet
the applicable standard; and
     Revised 40 CFR 63.7852 to add definitions for ``basic
oxygen process furnace group,'' ``mercury switch,'' ``motor vehicle,''
``motor vehicle scrap,'' ``opening,'' ``post-consumer steel scrap,''
``pre-consumer steel scrap,'' ``steel scrap,'' and ``scrap provider.''

F. What compliance dates are we proposing?

    Because most of these amendments provide corrections and
clarifications to the current rule and do not impose new requirements
on the industry, we are proposing that these amendments become
effective 180 days after promulgation of the final rule, except for the
provisions for mercury control via scrap selection or meeting scrap
input-based emission standards, for which we are requiring compliance
for existing sources within 1 year of promulgation. New sources,
defined to be new BOPF or facilities constructed or reconstructed after
August 16, 2019, are subject to the new source mercury limit on the
effective date of the final rule.
    We are proposing the 1-year existing source compliance date to
allow facilities to switch scrap suppliers, if needed, and become
familiar with the reporting requirements for scrap providers; for
facilities who would choose to comply with the input-based mercury
scrap limit, the compliance date was chosen so as to allow for