```

[Federal Register Volume 81, Number 70 (Tuesday, April 12, 2016)]
[Rules and Regulations]
[Pages 21671-21697]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-07818]

[[Page 21671]]

Vol. 81

Tuesday,

No. 70

April 12, 2016

Part II

Environmental Protection Agency

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40 CFR Part 52

Air Plan Approval; Minnesota and Michigan; Revision to 2013 Taconite 
Federal Implementation Plan Establishing BART for Taconite Plants; 
Final Rule

Federal Register / Vol. 81 , No. 70 / Tuesday, April 12, 2016 / Rules 
and Regulations

[[Page 21672]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R05-OAR-2015-0196; FRL-9944-22-Region 5]

Air Plan Approval; Minnesota and Michigan; Revision to 2013 
Taconite Federal Implementation Plan Establishing BART for Taconite 
Plants

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is finalizing a 
revision to the Federal implementation plan (FIP) addressing the 
requirement for best available retrofit technology (BART) for taconite 
plants in Minnesota and Michigan. In response to petitions for 
reconsideration, we are revising the nitrogen oxides (NOX) 
limits for taconite furnaces at facilities owned and operated by Cliffs 
Natural Resources (Cliffs) and ArcelorMittal USA LLC (ArcelorMittal). 
Cliffs owns and operates Tilden Mining and United Taconite. Hibbing is 
owned by Cliffs, ArcelorMittal and U.S. Steel and operated by Cliffs. 
ArcelorMittal is owner and operator of Minorca Mine. We are also 
revising the sulfur dioxide (SO2) requirements at two of 
Cliffs' facilities. We are making these changes because new information 
has come to light that was not available when we originally promulgated 
the FIP on February 6, 2013.

DATES: This final rule is effective on May 12, 2016.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-R05-OAR-2015-0196. All documents in the docket are listed in 
the www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available either in 
www.regulations.gov or at the Environmental Protection Agency, Region 
5, Air and Radiation Division, 77 West Jackson Boulevard, Chicago, 
Illinois 60604. This facility is open from 8:30 a.m. to 4:30 p.m., 
Monday through Friday, excluding Federal holidays. We recommend that 
you telephone Steven Rosenthal at (312) 886-6052 before visiting the 
Region 5 office.

FOR FURTHER INFORMATION CONTACT: Steven Rosenthal, Environmental 
Engineer, Attainment Planning & Maintenance Section, Air Programs 
Branch (AR-18J), U.S. Environmental Protection Agency, Region 5, 77 
West Jackson Boulevard, Chicago, Illinois 60604, (312) 886-6052, 
rosenthal.steven@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,'' 
``us,'' or ``our'' is used, we mean EPA. This section is arranged as 
follows:

I. Definitions
II. Background Information
III. Comments and Responses
IV. Revision to Equation for Normally Distributed but not 
Statistically Independent Data
V. What action is EPA taking?
VI. Statutory and Executive Order Reviews

I. Definitions

    For the purpose of this document, we are giving meaning to certain 
words or initials as follows:
     The initials BACT mean or refer to Best Available Control 
Technology.
     The initials BART mean or refer to Best Available Retrofit 
Technology.
     The initials CAA mean or refer to the Clean Air Act.
     The initials CBI mean or refer to Confidential Business 
Information.
     The initials CEMS means or refers to continuous emission 
monitoring system.
     The initials CFD mean or refer to computational fluid 
dynamic.
     The words EPA, we, us, or our mean or refer to the United 
States Environmental Protection Agency.
     The initials FIP mean or refer to Federal Implementation 
Plan.
     The initials LNB mean or refer to low-NOX 
burners.
     The initials MACT mean or refer to Maximum Achievable 
Control Technology.
     The initials MCEA means or refers to the Minnesota Center 
for Environmental Advocacy.
     The initials MMBtu mean or refer to million British 
thermal units.
     The initials MW mean or refer to megawatts.
     The initials NAAQS mean or refer to National Ambient Air 
Quality Standards.
     The initials NESHAP mean or refer to National Emission 
Standards for Hazardous Air Pollutants.
     The initials NSPS mean or refer to Standards of 
Performance for New Stationary Sources.
     The initials NOX mean or refer to nitrogen 
oxides.
     The initials NPCA means or refers to the National Parks 
Conservation Association.
     The initials NTAA means or refers to the National Tribal 
Air Association.
     The initials PRB mean or refer to the Powder River Basin.
     The initials RHR mean or refer to the EPA's Regional Haze 
Rule.
     The initials RMB mean or refer to RMB Consulting and 
Research.
     The initials SCR mean or refer to Selective Catalytic 
Reduction.
     The initials SIP mean or refer to State Implementation 
Plan.
     The initials SO2 mean or refer to sulfur 
dioxide.
     The initials UPL mean or refer to Upper Prediction Limit.

II. Background Information

A. Requirements of the Clean Air Act and EPA's Regional Haze Rule

    In section 169A of the 1977 Amendments to the CAA, Congress created 
a program for protecting visibility in the nation's national parks and 
wilderness areas. This section of the CAA establishes as a national 
goal the ``prevention of any future, and the remedying of any existing, 
impairment of visibility in mandatory Class I Federal areas \1\ which 
impairment results from manmade air pollution.'' Congress added section 
169B to the CAA in 1990 to address regional haze issues. EPA 
promulgated a rule to address regional haze on July 1, 1999. 64 FR 
35714 (July 1, 1999), codified at 40 CFR part 51, subpart P (herein 
after referred to as the ``Regional Haze Rule''). The RHR revised the 
existing visibility regulations to add provisions addressing regional 
haze impairment and established a comprehensive visibility protection 
program for Class I areas. The requirements for regional haze, found at 
40 CFR 51.308 and 51.309, are included in EPA's visibility protection 
regulations at 40 CFR 51.300-309.
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    \1\ Areas designated as mandatory Class I Federal areas consist 
of national parks exceeding 6000 acres, wilderness areas and 
national memorial parks exceeding 5000 acres, and all international 
parks that were in existence on August 7, 1977. 42 U.S.C. 7472(a). 
In accordance with section 169A of the CAA, EPA, in consultation 
with the Department of Interior, promulgated a list of 156 areas 
where visibility is identified as an important value. 44 FR 69122 
(November 30, 1979). The extent of a mandatory Class I area includes 
subsequent changes in boundaries, such as park expansions. 42 U.S.C. 
7472(a). Although states and tribes may designate as Class I 
additional areas which they consider to have visibility as an 
important value, the requirements of the visibility program set 
forth in section 169A of the CAA apply only to ``mandatory Class I 
Federal areas.'' Each mandatory Class I Federal area is the 
responsibility of a ``Federal Land Manager.'' 42 U.S.C. 7602(i). 
When we use the term ``Class I area'' in this action, we mean a 
``mandatory Class I Federal area.''
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B. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs states, or EPA if developing a FIP, 
to

[[Page 21673]]

evaluate the use of retrofit controls at certain larger, often 
uncontrolled, older stationary sources in order to address visibility 
impacts from these sources. Specifically, section 169A(b)(2)(A) of the 
CAA requires EPA to develop a FIP that contains such measures as may be 
necessary to make reasonable progress toward the natural visibility 
goal, including a requirement that certain categories of existing major 
stationary sources \2\ built between 1962 and 1977 procure, install, 
and operate the BART as determined by EPA. Under the RHR, states (or in 
the case of a FIP, EPA) are directed to conduct BART determinations for 
such ``BART-eligible'' sources that may reasonably be anticipated to 
cause or contribute to any visibility impairment in a Class I area.
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    \2\ The set of ``major stationary sources'' potentially subject 
to BART is listed in CAA section 169A(g)(7), and includes ``taconite 
ore processing facilities.''
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    On July 6, 2005, EPA published the Guidelines for BART 
Determinations Under the Regional Haze Rule at appendix Y to 40 CFR 
part 51 (hereinafter referred to as the ``BART Guidelines'') to assist 
states and EPA in determining which sources should be subject to the 
BART requirements and in determining appropriate emission limits for 
each applicable source. 70 FR 39104.
    The process of establishing BART emission limitations includes 
identifying those sources that meet the definition of ``BART-eligible 
source'' set forth in 40 CFR 51.301,\3\ determining which of these 
sources ``emits any air pollutant which may reasonably be anticipated 
to cause or contribute to any impairment of visibility in any such 
area'' (a source which fits this description is ``subject to BART''), 
and, for each source subject to BART, identifying the best available 
type and level of control for reducing emissions.
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    \3\ BART-eligible sources are those sources that have the 
potential to emit 250 tons or more of a visibility-impairing air 
pollutant, were not in operation prior to August 7, 1962, but were 
in existence on August 7, 1977, and whose operations fall within one 
or more of 26 specifically listed source categories. 40 CFR 51.301.
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    States, or EPA if developing a FIP, must address all visibility-
impairing pollutants emitted by a source in the BART determination 
process. The most significant visibility impairing pollutants are 
SO2, NOX, and particulate matter.
    A SIP or FIP addressing regional haze must include source-specific 
BART emission limits and compliance schedules for each source subject 
to BART. Once a state or EPA has made a BART determination, the BART 
controls must be installed and operated as expeditiously as 
practicable, but no later than five years after the date of the final 
SIP or FIP. See CAA section 169A(g)(4) and 40 CFR 51.308(e)(1)(iv). In 
addition to what is required by the RHR, general SIP requirements 
mandate that the SIP or FIP include all regulatory requirements related 
to monitoring, recordkeeping, and reporting for the BART controls on 
the source. See CAA section 110(a).

C. Regulatory and Legal History of the 2013 Taconite FIP

    On February 6, 2013, EPA promulgated a FIP (78 FR 8706) that 
included BART limits for taconite furnaces subject to BART in Minnesota 
and Michigan. EPA took this action because Minnesota and Michigan had 
failed to meet a statutory deadline to submit their Regional Haze SIPs 
and subsequently failed to require BART at the taconite facilities. 
Cliffs, ArcelorMittal, and the State of Michigan petitioned the Eighth 
Circuit Court of Appeals for review of the FIP, and, on May 17, 2013, 
Cliffs and ArcelorMittal filed a joint motion for stay of the final 
rule, which was granted by the Eighth Circuit on June 14, 2013, and is 
still in effect.
    EPA received petitions for reconsideration of the 2013 Taconite FIP 
from the National Mining Association on March 8, 2013, ArcelorMittal on 
March 22, 2013, the State of Michigan on April 1, 2013, Cliffs on April 
3, 2013, Congressman Richard M. Nolan on April 8, 2013, the State of 
Minnesota on April 8, 2013, and United States Steel Corporation (U.S. 
Steel) on November 26, 2013.
    In a related action, EPA published a final partial disapproval of 
the Michigan and Minnesota Regional Haze SIPs on September 30, 2013 (78 
FR 59825), for failure to require BART for SO2 and 
NOX emissions from taconite furnaces subject to BART. By 
petitions dated November 26, 2013, Cliffs and U.S. Steel petitioned EPA 
pursuant to section 307(d)(7)(B) of the CAA for reconsideration of 
EPA's partial disapproval of the Michigan and Minnesota Regional Haze 
SIPs. Further, Cliffs, ArcelorMittal, Michigan, and U.S. Steel 
petitioned the Eight Circuit Court of Appeals for review of the final 
rule partially disapproving the Michigan and Minnesota Regional Haze 
SIPs.
    EPA subsequently reached a settlement agreement with Cliffs, 
ArcelorMittal, and Michigan regarding issues raised by these parties in 
their petitions for review and reconsideration. Notice of the 
settlement was published in the Federal Register on January 30, 2015 
(80 FR 5111), and the settlement agreement was fully executed on April 
9, 2015. Pursuant to the settlement agreement, EPA granted partial 
reconsideration of the 2013 Taconite FIP on July 2, 2015, based on new 
information raised in Cliffs', ArcelorMittal's, and Michigan's 
petitions for reconsideration. EPA did not grant reconsideration of the 
2013 SIP disapprovals because EPA continues to believe that BART for 
taconite plants involves significant reductions of NOX and 
SO2 emissions that were not required in the Michigan and 
Minnesota SIPs.

III. Comments on Proposed Action and Responses

    On October 22, 2015, EPA published a Federal Register action 
entitled ``Air Plan Approval; Minnesota and Michigan; Revision to 
Taconite Federal Implementation Plan; Proposed Rule'' (80 FR 64160), 
which proposed to revise the 2013 Taconite FIP with respect to the BART 
emission limitations and compliance schedules for the following 
taconite plants: United Taconite, Hibbing Taconite, Tilden Mining, and 
ArcelorMittal Minorca Mine. Cliffs is the owner and operator of the 
United Taconite and Tilden Mining facilities and part owner and 
operator of Hibbing Taconite. ArcelorMittal is the owner and operator 
of the Minorca Mine facility and a part owner of the Hibbing Taconite 
facility.
    EPA proposed to revise the NOX limits and compliance 
schedules for all four facilities and to revise the SO2 
requirements for Tilden Mining and United Taconite in response to new 
information that became available after the close of the public comment 
period of the 2013 FIP. Specifically, Cliffs and ArcelorMittal 
submitted information to EPA that suggested high-stoichiometric LNBs, 
which formed the basis of the original NOX limits, posed 
serious technical hurdles. Consequently, EPA proposed to determine that 
BART for taconite facilities was low-stoichiometric LNBs (for grate 
kilns) and a combination of water and steam injection and pre-
combustion technologies (for straight-grate kilns) and proposed revised 
NOX limits based upon these technologies. Cliffs also 
submitted information showing that United Taconite could not burn very 
low-sulfur coal without challenges and that Tilden intended to burn 
mixed low-sulfur fuels instead of 100% natural gas. As a result, EPA 
proposed to revise the SO2 limits for these facilities.
    The public comment period on the proposal ended on December 23, 
2015. EPA received comments from the National Park Service of the 
United

[[Page 21674]]

States Department of Interior, the National Parks Conservation 
Association (NPCA), the Minnesota Center for Environmental Advocacy 
(MCEA), United States Steel Corporation, ArcelorMittal USA LLC, the 
Forest Service of the United States Department of Agriculture (USDA), 
Cliffs Natural Resources, and the Fond du Lac Band of Lake Superior 
Chippewa. The National Tribal Air Association (NTAA) requested an 
extension of the public comment period of 120 days. A 30-day extension 
of the public comment period was provided, but NTAA did not 
subsequently submit comments. EPA fully considered all of the comments 
and responds to each comment below. Based on our consideration of the 
comments, we are finalizing the NOX and SO2 
emission limits and compliance schedules as proposed, with two minor 
exceptions explained in Section V.

A. Comments by the Forest Service

    Comment: The Forest Service disagreed with EPA's determination that 
LNBs should be eliminated as a potential BART option for straight-grate 
kilns. The Forest Service stated that LNBs are included in the permits 
for straight-grate furnaces for Essar Steel (Essar) in Minnesota and 
Magnetation in Indiana, which (unlike Essar) has commenced operation. 
The permit limits for each of the two LNB-equipped straight-grate kilns 
are 0.25 lbs NOX/MMBTU, which is lower than the limits 
proposed by EPA.
    Response: EPA disagrees that the situations at Essar and 
Magnetation provide sufficient evidence that LNBs would be technically 
feasible at the Minorca Mine and Hibbing facilities. Essar and 
Magnetation were subject to the BACT requirement that applies to new 
and modified sources. Consequently, these facilities were able to 
integrate LNBs into the design and construction of their furnaces. In 
contrast, the furnaces at Minorca Mine and Hibbing were not designed to 
accommodate LNBs. As discussed in the proposal, EPA eliminated LNBs 
from consideration due to the technical challenges associated with a 
retrofit application on the unique straight-grate kilns at Minorca Mine 
and Hibbing. We also note that the Essar straight-grate furnace is 
still not operational, and Magnetation is not an iron ore processing 
facility and therefore is not classified as a taconite facility as 
defined by the taconite MACT (40 CFR part 63 subpart RRRRR). While 
Magnetation's permit limit is 0.25 lbs NOX/MMBTU, the 
results from an August-September 2015 test indicate emissions ranging 
from 0.773 lbs NOX/MMBTU to 1.304 lbs NOX/MMBTU 
at that facility. Finally, we note that we are finalizing an initial 
emission limit of 1.2 lbs NOX/MMBTU (subject to upward 
revision only in unlikely scenarios) for the Minorca Mine and Hibbing 
furnaces, which is consistent with the limit in our 2013 FIP, but based 
on the installation of different technologies.
    Comment: The Forest Service stated that EPA seems to assume that 
the only way to meet the existing 0.6 percent sulfur limit is to use 
western sub-bituminous coal, which will not work in the furnace due to 
its lower heating value. The Forest Service did a quick search of U.S. 
coal data (US DOE, NETL, Detailed Coal Specifications, Quality 
Guidelines for Energy System Studies, Final Report, DOE/NETL-401/
012111, January 2012, page 31) and could find no eastern bituminous 
coal at 0.6 percent sulfur, but was able to find a low-volatile, 
eastern bituminous coal with very high heating value at 0.66 percent 
sulfur, which is far below the new limit proposed by EPA for United 
Taconite of 1.5 percent sulfur. The Forest Service stated that if an 
adjustment is warranted to the existing limit, it should be based on 
low-sulfur content eastern bituminous coal, such as the one at 0.66 
percent sulfur.
    Response: EPA disagrees with this comment. The primary 
SO2 emission limit for BART at United Taconite is the 529 
lbs SO2/hr aggregate limit on lines 1 and 2. This BART 
limit, which is based upon the use of low-sulfur fuels (a combination 
of natural gas and coal), will result in 1900 tons per year of 
SO2 reductions. In contrast, the 1.5 percent sulfur limit is 
an operational limit that EPA imposed after Cliffs requested an 
adjustment to its baseline emission rate to be used in evaluating 
potential BART controls. Under the BART guidelines, the baseline 
emission rate ordinarily should represent a realistic depiction of 
anticipated annual emissions for the source based upon actual emissions 
from a baseline period. See 40 CFR part 51, appendix Y. However, when 
future operating parameters, such as type of fuel, will differ from 
past practice, and if this projection has a deciding effect in the BART 
determination, then the operating parameter must be made into an 
enforceable limitation. Id. EPA imposed the original 0.60 percent 
sulfur limit on the coal burned at United Taconite to comply with this 
provision. However, Cliffs indicated in its petition for 
reconsideration that 0.60 percent sulfur coal posed several issues for 
its furnaces. As a result, the EPA proposed to increase the operational 
limit to 1.5 percent sulfur, but this change will not have an effect on 
emissions at United Taconite due to the 529 lbs SO2/hr 
limit. In essence, United Taconite will now be required to burn more 
natural gas and less coal (or all gas) to meet its BART limit than the 
facility would have under a 0.60 percent sulfur limit.
    Comment: The Forest Service asked for an explanation as to why 
Minorca Mine and Tilden have the longest deadlines for compliance when 
they each have only one furnace at their facility.
    Response: To establish an overall compliance schedule that is as 
expeditious as practicable, we grouped the furnaces according to 
whether they are straight-grate kilns or grate kilns, not according to 
which facility they belong. By grouping furnaces according to design 
and function rather than facility, Cliffs and ArcelorMittal will be 
able to take advantage of the experience gained from the first 
installation of NOX reduction technologies at a straight-
grate kiln and grate kiln at the other furnaces. For example, Tilden 
will be able to take advantage of the experience of the earlier 
installation of a low-stoichiometric LNB on a grate kiln at United 
Taconite, while ArcelorMittal will be able to take advantage of the 
earlier installation of NOX reduction technologies on a 
straight-grate kiln at Hibbing. We believe that this staggered schedule 
is necessary because, although the selected NOX controls 
have been subject to extensive engineering studies, they have not been 
used on taconite furnaces in the United States to date. Such experience 
is necessary to ensure proper operation of these furnaces. Improper 
burner operation could adversely affect heat distribution throughout 
the furnace as well as pellet quality.
    Comment: The Forest Service stated that it would like the 
opportunity to review and comment on the final emission limits.
    Response: EPA has provided an extremely detailed and objective 
step-by-step procedure that will be used for determining the final 
emission limits. The notice of proposed rulemaking provided adequate 
information about the basis and timing of the final limits such that no 
further proposals will be necessary. The equations and an explicit 
explanation of how the final limits will be established are contained 
in the proposal, so the Forest Service could have raised any concerns 
during the public comment period. EPA is taking this approach in order 
to expedite the establishment of final enforceable limits for these 
facilities within the context of a process that provides reasonable 
time to design and install emission controls,

[[Page 21675]]

to obtain data needed for determining control effectiveness, and to 
minimize the time then needed to establish final enforceable limits. 
EPA has carefully considered the Forest Service's comments, but does 
not believe that a second comment period is necessary.
    Comment: The Forest Service requested a description of how plant 
shutdowns will be handled.
    Response: EPA is unsure what the commenter means by ``plant 
shutdowns,'' but presumes that the Forest Service may be concerned that 
the emission limits could be relaxed during a shutdown. No special 
consideration has been given to plant shutdowns in this respect. The 
NOX limits are based on the production level and the 
quantity of fuel burned.
    Comment: The Forest Service asked EPA to describe what will be done 
if adequate data are not collected within the timeframe envisioned in 
the schedule to establish a final emission limit.
    Response: The eight-month testing period, during which controls 
will be in place and CEMS will be operational, should provide ample 
time for collecting data adequate to establish a final limit.
    Comment: The Forest Service asked EPA to specify what design 
parameters will be monitored for the different control technologies.
    Response: The design parameters will be established in the 
engineering reports that are required by the settlement agreement and 
this action. We anticipate that the percent stoichiometric primary 
combustion air and gas/coal ratio when co-firing will be important 
variables.

B. Comments by the National Park Service

    Comment: The National Park Service, as well as NPCA and MCEA, 
commented on the technical feasibility of controlling NOX 
using SCR and encouraged EPA to further evaluate various configurations 
of SCR, including tail-end SCR with gas stream reheat (hereinafter 
referred to as ``SCR with reheat'').
    Response: There are several air pollution control technology 
analyses involving the potential use of SCR and SCR with reheat on 
indurating furnace hood exhaust. In these analyses (Magnetation BACT, 
Essar BACT, and Tilden BART), SCR with reheat was rejected for not 
being cost-effective, while upstream SCR was rejected as technically 
infeasible due to the likelihood that the exhaust stream would foul the 
catalyst.
    In a study conducted by Hatch for U.S. Steel, SCR with reheat was 
considered as a potential control option, but further discussion with 
potential vendors resulted in the determination that SCR with reheat is 
not a technically feasible control option for taconite indurating 
furnaces. One potential vendor, Mitsubishi Power Systems, cited 
temperature and layout as factors rendering SCR with reheat less than 
optimal for NOX control from U.S. Steel's Minntac taconite 
indurating furnaces. LKAB, a taconite facility in Sweden, has an SCR 
with reheat on its KK4 taconite pelletizing line. Alstom, the SCR 
vendor for LKAB, declined twice to bid on an SCR with reheat at 
Minntac, citing technical difficulties with the SCR with reheat at 
LKAB. These difficulties included operating within the narrow 
temperature range required by SCR with reheat. Further, LKAB is looking 
into process optimization and better burners to reduce NOX 
as opposed to installing another SCR with reheat in the future. It is 
important to note that SCR with reheat, even if it were technically 
feasible, would result in additional energy and environmental costs in 
the form of increased usage of natural gas and greenhouse gas 
emissions, respectively. While increased energy and environmental 
penalties are not preclusive, they further weigh against any additional 
analysis of SCR with reheat as a viable option for indurating furnaces 
at this time. We expect Minnesota and Michigan to reevaluate SCR with 
reheat as a potential option for making reasonable progress in future 
planning periods, but reject the technology as BART for the Minnesota 
and Michigan taconite facilities at this time.
    Comment: The National Park Service concurred with the maximum 3.0 
lbs NOX/MMBTU limit when burning natural gas only at grate 
kilns. However, the National Park Service did not believe that allowing 
NOX emissions to increase by 87 percent above expected 
levels when burning a gas/coal mix at grate kilns is justified.
    Response: Low-stoichiometric LNBs, as designed by FCT Combustion 
(FCT), are designed to reduce NOX while maintaining pellet 
quality and production and optimizing fuel efficiency. As a result, 
this LNB was selected to establish BART limits for Cliffs' grate-kiln 
furnaces. FCT's computational fluid dynamic (CFD) modeling for co-
firing at 30 percent gas and 70 percent coal indicated a reduction from 
a base case of 1.6-5.4 lbs NOX/MMBTU with a typical baseline 
value of 2.5 lbs NOX/MMBTU, to 2.04 lbs NOX/
MMBTU. Therefore, an increase from 2.04 to 2.5 lbs NOX/MMBTU 
is a 23 percent increase above expected levels, which is more 
meaningful than the 67 percent increase (not 87 percent) above the low 
end of the range of the final emission limits. It should be noted that, 
in addition to the uncertainty resulting from the lack of experience in 
the use of low-stoichiometric LNBs, there is additional uncertainty 
because the CFD modeling was only performed for co-firing at 30 percent 
gas and 70 percent coal. Furthermore, a rigorous demonstration would 
have to be made that 1.5 lbs NOX/MMBTU cannot be met before 
the limit is adjusted and an alternative final limit is set.
    Comment: The National Park Service was concerned that, although the 
proposed FIP requires the NOX reduction technologies for the 
straight-grate furnaces at Minorca Mine and Hibbing be designed to meet 
a limit of 1.2 lbs NOX/MMBTU, EPA is proposing to increase 
the final limit up to 1.8 lbs NOX/MMBTU if a rigorous 
demonstration is made that the 1.2 lbs NOX/MMBTU limit 
cannot be met. This represents a 50 percent increase above the expected 
emission rate and no justification is provided for such a large 
``safety margin.''
    Response: As discussed in the proposed rulemaking, EPA is confident 
that Minorca Mine and Hibbing can meet a limit of 1.2 lbs 
NOX/MMBTU based upon the engineering report prepared for 
ArcelorMittal that assesses the use of water and steam injection and 
pre-combustion technologies. However, because this suite of 
technologies has not previously been used on straight-grate kilns, some 
uncertainty remains regarding the potential effect on pellet quality. 
As a result, EPA has provided a procedure by which the final limits for 
Minorca Mine and Hibbing could be revised upwards to as much as 1.8 lbs 
NOX/MMBTU. It is important to note, however, that EPA has 
included rigorous requirements that must be met before any relaxing of 
the initial 1.2 lbs NOX/MMBTU limit would be allowed.
    Comment: The National Park Service stated that EPA has the 
authority to limit the sulfur content of the fuels already fired at 
United Taconite. The National Park Service understood that United 
Taconite has identified problems with the characteristics of the 0.6 
percent sulfur coal originally proposed by EPA and the compatibility of 
that coal with the United Taconite furnace. The National Park Service 
cited EPA's statement that it ``is also establishing a limitation on 
the coal to be used by requiring the coal have a sulfur content

[[Page 21676]]

no greater than 1.5 percent sulfur by weight based on a monthly block 
average.'' However, the National Park Service stated that it is aware 
of eastern bituminous coals that have much lower sulfur contents and 
requested that EPA evaluate the potential for combustion of such coals 
at United Taconite.
    Response: EPA disagrees with this comment. The primary 
SO2 emission limit for BART at United Taconite is the 529 
lbs SO2/hr aggregate limit on lines 1 and 2. This BART 
limit, which is based upon the use of low-sulfur fuels (a combination 
of natural gas and coal), will result in 1900 tons per year of 
SO2 reductions. In contrast, the 1.5 percent sulfur limit is 
an operational limit that EPA imposed after Cliffs requested an 
adjustment to its baseline emission rate to be used in evaluating 
potential BART controls. Under the BART guidelines, the baseline 
emission rate ordinarily should represent a realistic depiction of 
anticipated annual emissions for the source based upon actual emissions 
from a baseline period. See 40 CFR part 51, appendix Y. However, when 
future operating parameters, such as type of fuel, will differ from 
past practice, and if this projection has a deciding effect in the BART 
determination, then the operating parameter must be made into an 
enforceable limitation. Id. EPA imposed the original 0.60 percent 
sulfur limit on the coal burned at United Taconite to comply with this 
provision. However, Cliffs indicated in its petition for 
reconsideration that 0.60 percent sulfur coal posed several issues for 
its furnaces. As a result, the EPA proposed to increase the operational 
limit to 1.5 percent sulfur, but this change will not have an effect on 
emissions at United Taconite due to the 529 lbs SO2/hr 
limit. In essence, United Taconite will now be required to burn more 
natural gas and less coal (or all gas) to meet its BART limit than the 
facility would have under a 0.60 percent sulfur limit.
    Comment: The National Park Service stated that EPA was apparently 
proposing to use hourly emission rates measured by a CEMS to derive the 
UPL. The National Park Service questioned the appropriateness of basing 
the UPL on hourly values if EPA is setting a 30-day (or 720-hour) 
rolling average limit. The National Park Service was concerned that the 
use of hourly values would introduce excess variability into the 
calculation and could lead to a higher UPL.
    Response: When the UPL equation for normally distributed and 
statistically independent data is used, the average , standard 
deviation (s), and number of values (n) are based on the hourly data. 
The term number of values used to calculate the test average) is based 
on the compliance period, i.e., 720 for a 720-hour average and not 1. 
This results in a lower and more stringent UPL than if 1. However, when 
setting a 720-hour average emission limit using the nonparametric 
equation, the data set used would be the 720-hour averages rather than 
the raw hourly data.

C. Comments by the National Parks Conservation Association (NPCA)

1. NPCA Incorporated the Comments Submitted by the National Park 
Service
    Comment: NPCA restated the National Park Service comments as 
follows:

--SCR remains a feasible technical option for limiting NOX 
from taconite facilities. While two SCR vendors declined to bid on the 
NOX reduction testing at Minntac, this is an insufficient 
basis to reject SCR across the taconite industry. EPA should revisit 
this decision and evaluate various configurations of SCR that would 
serve to further reduce NOX emissions beyond the limits in 
the proposed settlement.
--EPA's proposed NOX limits for the gas/coal scenario at 
United Taconite and Tilden are improper because they are up to 87 
percent higher than the limits in the 2013 FIP.
--EPA's proposed NOX limits for Hibbing and Minorca Mine are 
improper because they are up to 50 percent higher than the limits in 
the 2013 FIP.
--EPA should require the use of an alternative low-sulfur coal at 
United Taconite.

    Response: EPA has responded in detail to these comments in 
responses to the comments by the National Park Service (see above).
    Comment: NPCA stated that the proposal specifies that increased 
limits are permissible where the industry makes a rigorous 
demonstration that lower limits cannot be met. NPCA requested that any 
such demonstration be made available to the public for review and 
comment.
    Response: EPA has provided an extremely detailed and objective 
step-by-step procedure for determining the final emission limits. The 
notice of proposed rulemaking provided adequate information about the 
basis and timing of the final limits such that no further proposals 
will be necessary. EPA is taking this approach in order to expedite the 
establishment of final enforceable limits for these facilities within 
the context of a process that provides reasonable time to design and 
install emission controls, to obtain data needed for determining 
control effectiveness, and to minimize the time then needed to 
establish final enforceable limits. The proposal encouraged commenters 
to comment on any issues that might be anticipated to arise at any 
point in the process described in the proposal, and NPCA has not 
identified any such issues.
2. NPCA Incorporated Its March 2, 2015 Comments Regarding the 
Settlement Agreement
    Comment: NPCA stated that the changes in emission limits between 
the 2013 FIP and the settlement agreement appear to significantly 
weaken the terms of the 2013 FIP because the emission limits are far 
less stringent. Although NPCA did not have the necessary level of 
detailed information to perform a precise comparison, NPCA's rough 
calculations indicated that the limitations in attachment A of the 
settlement agreement would allow for pollution at or above the actual 
baseline emissions from the taconite facilities, that is, they 
represent no reduction (or at a minimum, no significant reduction) in 
pollution.
    Response: As discussed in the five-step BART determinations in the 
proposal, there are significant emission reductions from the revised 
limits. There will be an estimated total of 3,000 tons per year of 
NOX reductions from Tilden and United Taconite, a total of 
7,400 tons per year of NOX reductions from Minorca Mine and 
Hibbing, 1,900 tons per year of SO2 reductions from United 
Taconite, and 300 tons of SO2 reductions from Tilden. The 
only NOX emission limits that are definitely less stringent 
than those in the 2013 FIP are the NOX emission limits for 
Tilden and United Taconite when burning solely natural gas. The final 
NOX emission limits for Hibbing and Minorca Mine, as well as 
Tilden and United Taconite when co-firing coal and natural gas, are 
expected to be the same as, or close to, the 2013 FIP limits. There may 
also be an increase in SO2 emissions from Tilden, but this 
should be a fairly small increase as Tilden will be solely burning 
natural gas and very low (0.6 percent) sulfur coal.
    Comment: NPCA argued that the timeframes for compliance are 
significantly longer than in the 2013 FIP.
    Response: The compliance schedule is generally similar to the FIP 
except that implementation has been delayed because of the court-
imposed stay. The main differences between the two schedules are that 
Tilden must install controls within 50 months (compared with 26 months 
in the 2013 FIP) and Minorca Mine must install controls

[[Page 21677]]

within 44 months (compared with 26 months in the 2013 FIP). The 
staggered compliance schedule, which includes additional time for 
Tilden and ArcelorMittal, is necessary because the NOX 
controls selected as BART have not been used on taconite furnaces in 
the United States. Such experience is necessary to ensure proper 
operation of these furnaces. The planned controls could adversely 
affect heat distribution throughout the furnace as well as pellet 
quality.
    Comment: NPCA stated that, in proposing the settlement, EPA offered 
no support to suggest why such a significant weakening of much needed 
and statutorily required limits was appropriate. NPCA was thus at a 
loss to comment on the rationale behind the changes.
    Response: As discussed in a prior response, EPA does not agree that 
there has been a significant weakening of the requirements for taconite 
facilities. EPA's basis for all changes was contained in the proposed 
FIP revision and its associated docket.
    Comment: NPCA stated that EPA must provide documentation of the 
reasons for the proposed changes in the form of publicly available 
information. EPA cannot rely strictly on confidential information, 
which does not allow the public to review and consider the changes 
proposed.
    Response: Publicly available information in support of the FIP is 
contained in the docket.
    Comment: NPCA stated that the settlement referenced ``equitable 
treatment of facilities not included in this settlement.'' This would 
appear to refer to the taconite facilities covered by the 2013 FIP but 
not included in the settlement. To the extent that this statement 
refers to the potential weakening of limits imposed at other facilities 
in the taconite FIP, the increase in pollution that appears in the 
settlement is all the more concerning.
    Response: EPA has not proposed to change the emission limits for 
other facilities covered by the 2013 FIP at this time.
    Comment: NPCA stated that the timeframe for compliance detailed in 
the settlement agreement was inappropriate. The CAA requires that 
controls required under BART be implemented within five years of the 
final rule. In this case, the rule was finalized in January 2013, so 
compliance with emission limits must be by January 2018.
    Response: We disagree with this comment. Section 169A(g)(4) of the 
CAA requires compliance with BART emission limits no later than five 
years after ``the date of promulgation of a . . . [FIP] revision.'' In 
this final rule, we are promulgating a revision to the 2013 FIP that 
includes new BART determinations based on new technologies. These BART 
determinations fully supersede the determinations that were made in the 
2013 FIP. The taconite facilities must comply with the new BART 
emission limits in a staggered schedule that we have determined is as 
expeditious as practicable. Full compliance at all facilities will be 
achieved no later than five years from the date of the promulgation of 
this FIP revision.

D. Comments by Cliffs Natural Resources

    Comment: Cliffs supported the proposed FIP, including the initial 
limits, the staggered compliance schedule, and the formula for setting 
final limits if the initial limits cannot be achieved without adverse 
impacts on pellet quality. However, Cliffs objected to EPA's statement 
in the proposed FIP preamble that ``there are no significant costs or 
environmental impacts'' associated with the selected BART technologies. 
Cliffs will be required to expend millions of dollars to design and 
implement changes to its furnaces. There are also costs associated with 
lost production during downtime and shakedown, as well as the potential 
for additional fuel consumption when the BART technologies are 
operational.
    Response: EPA acknowledges that there will be costs associated with 
the BART control technologies employed by Cliffs. EPA's full statement 
in the preamble was that ``there are no significant costs or 
environmental impacts associated with this technology that would 
necessitate its elimination from consideration as BART.'' EPA continues 
to believe that the costs, energy, and non-air quality impacts 
associated with the selected BART controls are reasonable.
    Comment: Cliffs stated that EPA's proposal included a new 
requirement to report CEMS and pellet quality data at the end of a 
period that did not fall within the preceding calendar quarter within 7 
days of the close of the period. Reporting this information within 7 
days is impracticable, as it does not provide the facility sufficient 
time to complete the appropriate laboratory analysis and quality 
assurance expected for the data. Cliffs acknowledged EPA's need to 
include a provision to address the timely reporting of data, but 
requested that the reporting obligation be changed from 7 days to 30 
days to allow for quality assurance checks.
    Response: Using United Taconite Line 2 as an example, the 
settlement agreement states that, 44 months from the effective date of 
the rule, Cliffs must provide results from pellet quality analyses no 
later than 30 days from the end of each calendar quarter until 52 
months from the effective date of the rule. No later than 55 months 
after the effective date of the rule, EPA will take final agency action 
by publishing the NOX limits in the Federal Register. 
Assuming that the effective date of the rule is June 15, 2016, then 52 
months from the effective date is October 15, 2020, and 55 months is 
January 15, 2021. The end of the quarter would be December 31, 2020, so 
under the settlement language, the pellet quality data from October 1 
through October 15, 2020, would not be due until January 30, 2021, 
which is too late to be considered in establishing the final emission 
limit. According to the language in the proposal, the pellet quality 
analyses would need to be submitted to EPA by October 22, 2020. 
Accepting Cliffs' suggested revision from 7 to 30 days would require 
the pellet quality analysis to be submitted to EPA by November 14, 
2020. EPA accepts Cliffs' basis for increasing the reporting 
requirement from 7 to 30 days and will make this revision in the final 
FIP because it will not significantly interfere with expeditiously 
setting the final limits.
    Comment: Cliffs stated that United Taconite's pellet quality 
reporting obligations in the proposed FIP mistakenly refer to 
``Tilden's ISO 9001 quality management system'' but should refer to 
``United Taconite's ISO 9001 quality management system.''
    Response: EPA acknowledges the error and has made the correction in 
the final FIP.

E. Comments by the Fond du Lac Band of Lake Superior Chippewa

    Comment: The Band urged a fair, scientifically sound, and feasible 
process for all stakeholders, including affected and surrounding 
communities. The taconite industry should not be allowed to dictate its 
own compliance schedule or prolong compliance with Federal laws and 
regulations.
    Response: EPA agrees with this comment and has implemented a 
process to establish final BART limits based upon the most current, 
relevant, and scientifically sound information available. The taconite 
plant owners were in a unique position to acquire and provide the 
needed scientific information and understandably had motivation to do 
so. However, they are not dictating their own compliance schedule.

[[Page 21678]]

    Comment: The Band argued that the emission limits in the 2013 FIP 
are more reasonable in terms of protecting visibility than the limits 
proposed in the revised FIP.
    Response: While we acknowledge that a few of the emission limits in 
the 2013 FIP were more stringent than the limits in our proposed FIP 
revision, and were thus more protective of visibility, we disagree that 
the original limits were more reasonable. For the reasons explained in 
our proposal, new information provided by the taconite companies shows 
that the technology on which the 2013 FIP limits were based, high-
stoichiometric LNBs, would adversely affect pellet quality. As a 
result, we proposed new BART determinations based on new technologies. 
These technologies will still result in significant emission 
reductions, improving visibility in the Class I areas in Minnesota and 
Michigan.
    Comment: The Band stated that the compliance schedule in the 2013 
FIP was more reasonable from a health protection standpoint. The Band 
stated that it preferred the 2013 FIP schedule over the longer 
compliance schedule in the proposed FIP revision. Alternatively, a 
compromise schedule between the original schedule and the proposed 
schedule would be acceptable.
    Response: Please see our response to a similar comment from NPCA.
    Comment: The Band stated that Eastern bituminous coals are 
available that could meet both the requirements for a low-sulfur coal 
(0.66%) and a very high heating value (US DOE, NETL, Detailed Coal 
Specifications, Quality Guidelines for Energy System Studies, Final 
Report, DOE/NETL-401/012111, January 2012, page 31).
    Response: Please see our response to a similar comment from the 
Forest Service.
    Comment: The Band stated that SCR is considered the best available 
retrofit technology that has been used at other coal facilities and 
could feasibly reduce NOX emissions for taconite furnaces. 
The Band agreed with the National Park Service that the use of tail-end 
SCR with steam reheat should be evaluated for BART.
    Response: Please see our response to a similar comment from the 
National Park Service.
    Comment: The Band noted that EPA proposed to set limits for United 
Taconite and Tilden of 3.0 lbs NOX/MMBTU when burning 
natural gas and 2.5 lbs NOX/MMBTU when burning a gas/coal 
mix if the presumptive limits of 2.8 lbs NOX/MMBTU and 1.5 
lbs NOX/MMBTU, respectively, cannot be met. The Band noted 
that a limit of 2.5 lbs NOX/MMBTU (gas coal mix) is 67 
percent higher than the predicted emission rate of 1.5 lbs 
NOX/MMBTU. The Band acknowledged that some uncertainty is 
involved in developing the use of a new control technology, but argued 
that this range of emission limits is too large.
    Response: Please see our response to a similar comment from the 
National Park Service.
    Comment: The Band stated that EPA recently implemented a national 
policy on Environmental Justice for Working with Federally Recognized 
Tribes and Indigenous Peoples. EPA must uphold its duties to protect 
the interests of tribes and their treaty rights and explain how the 
proposed FIP complies with EPA's existing guidance and policies with 
Federally Recognized Tribes and Indigenous Peoples.
    Response: The U.S. Constitution defines treaties as part of the 
supreme law of the land with the same legal force as Federal statutes. 
Treaties are to be interpreted in accordance with the Federal Indian 
canons of construction, a set of long-standing principles developed by 
courts to guide the interpretation of treaties between the U.S. 
government and Indian tribes. As the Supreme Court has explained, 
treaties should be construed liberally in favor of tribes, giving 
effect to the treaty terms as tribes would have understood them, with 
ambiguous provisions interpreted for their benefit. Only Congress may 
abrogate Indian treaty rights, and courts will not find that abrogation 
has occurred absent clear evidence of congressional intent.
    EPA has committed to consider all relevant information obtained 
during tribal consultation to help ensure that EPA's actions do not 
conflict with treaty rights, to help ensure that EPA is fully informed 
when it seeks to implement its programs, and to further protect treaty 
rights and resources when it has discretion to do so. We have done so 
in this action. EPA consulted and coordinated with tribal officials and 
provided information on both the 2012 FIP proposal and the current 
taconite FIP proposal early in the process of developing this 
regulation in order to allow tribal governments to have meaningful and 
timely input. EPA provided information to tribes on the rationale for 
proposing this regulation in the absence of the states submitting 
plans, the potential health and environmental impacts associated with 
these facilities, and the emissions reductions to be gained from 
implementing this regulation. EPA also took into consideration the 
concerns and needs identified by tribal governments during this 
process. These consultation and education and outreach efforts began in 
August 2012 and continue through the present utilizing forums such as 
monthly tribe-EPA conference calls, presentations during annual 
meetings and conferences, and one-to-one discussions with EPA subject 
matter experts as requested.
    EPA's revision of the FIP is expected to have significant 
environmental benefits relative to the SIPs submitted by Michigan and 
Minnesota. On-and off-reservation trust resources held by Minnesota 
tribes (and other tribes), as recognized in treaties and in Minnesota 
v. Mille Lacs Band, 526 U.S. 172 (1999), among other authorities, will 
be protected to a greater extent by the controls required in the 
amended FIP.

F. Comments by ArcelorMittal

    Comment: ArcelorMittal cited to the preamble to the proposed FIP 
revision, which states that ``there are no significant costs or 
environmental impacts'' associated with the BART determinations for 
Hibbing and Minorca. However, in actuality, the changes necessary to 
meet the proposed emission limits will not be without costs and 
environmental impacts. ArcelorMittal will be required to expend 
millions of dollars to design and implement changes to its straight-
grate furnaces. It will also incur substantial costs associated with 
lost production during downtime and shakedown when these technologies 
are installed. Once operational, fuel penalties are expected which will 
result in increased cost.
    Response: EPA acknowledges that there will be costs associated with 
the BART control technologies employed by ArcelorMittal. EPA's full 
statement in the preamble was that ``there are no significant costs or 
environmental impacts associated with this technology that would 
necessitate its elimination from consideration as BART.'' EPA continues 
to believe that the costs, energy, and non-air quality impacts 
associated with the selected BART controls are reasonable.

G. Comments by United States Steel

    U.S. Steel submitted the following comments to ensure that EPA's 
approach to amending the original FIP is applied evenly and fairly and 
results in a consistent approach to BART for the taconite industry.
    Comment: U.S. Steel agreed with EPA's decision to develop a case-
by-case approach to BART for indurating furnaces and the Agency's 
proposed approach to determining BART for each

[[Page 21679]]

individual affected unit, based upon that unit's design and unit-
specific characteristics.
    Response: EPA appreciates U.S. Steel's support.
    Comment: U.S. Steel stated that a similar approach will be 
necessary for U.S. Steel's Minntac and Keetac furnaces.
    Response: This comment is outside the scope of this rulemaking.
    Comment: U.S. Steel stated that EPA should consider delaying 
finalization of the proposed FIP revision until EPA is prepared to 
promulgate similar amendments for all furnaces in the taconite 
industry.
    Response: EPA is bound by a settlement agreement to finalize the 
proposed FIP revision by March 18, 2016. Furthermore, there have 
already considerable delays in the implementation of BART for taconite 
indurating furnaces.
    Comment: U.S. Steel stated that if EPA does not delay finalization 
of the proposed FIP revision, EPA should continue the stay of effective 
dates in the original 2013 FIP pending completion of a similar FIP 
amendment for U.S. Steel's Minntac and Keetac facilities.
    Response: This comment is outside the scope of this rulemaking.
    Comment: U.S. Steel stated that EPA should clarify that U.S. Steel 
is part owner of Hibbing taconite.
    Response: EPA acknowledges that U.S. Steel is a part owner of the 
Hibbing facility.
    Comment: U.S. Steel identified four points made by EPA with which 
U.S. Steel disagrees and could not find substantiating information in 
the docket. These points are: (1) The smaller preheat burners at 
Minntac achieve very low NOX emissions rates (0.1-0.3 lbs 
NOX/MMBTU) due to a more favorable NOX reduction 
combustion environment in the preheat zone as compared to the firing 
end of the kiln; (2) ported kilns significantly change the heat balance 
of the furnace; (3) differences in the magnetite content of the ore 
body used by Minntac and United Taconite are significant; and 4) high-
stoichiometric LNBs will require more fuel and result in higher 
NOX emissions.
    Response: The basis for the above points questioned by U.S. Steel 
is presented in the proposed FIP at 80 FR 64163, which is in turn based 
upon the November 26, 2013 declaration by Eric Wagner, the Manager of 
Process Engineering for Metso Minerals Pyro Division, a ``global expert 
in the design of iron ore pelletizing furnaces.'' This declaration is 
attached to Cliffs' November 26, 2013 Petition for Administrative 
Reconsideration of the Partial Disapproval of Air Quality 
Implementation Plans for Regional Haze for the States of Michigan and 
Minnesota. Although a hard copy of this document was included in EPA's 
Regional docket, and available for inspection at EPA's Region 5 office, 
EPA mistakenly did not include this Petition for Reconsideration in the 
electronic docket for this rule until after the comment period had 
closed. U.S. Steel's comment questions the basis for several of Eric 
Wagner's statements regarding factors affecting indurating furnace 
operation and NOX emissions. We do not believe this omission 
was material, however, because U.S. Steel is seeking information, not 
challenging or suggesting revisions to the proposal.
    Comment: U.S. Steel stated that EPA should reconsider the partial 
disapproval of Minnesota's SIP.
    Response: This comment is outside the scope of this rulemaking.
    Comment: U.S. Steel stated that, for each of the affected 
facilities, there is a schedule prescribed for installation of the 
technology and period to collect data to confirm or adjust the limit 
based upon the data. The period allows for eight months of data 
collection. If an affected facility elects to install the technology 
earlier than prescribed by rule, the facility should have the ability 
to utilize a more robust data set greater than the eight months 
specified. Due to seasonal variations, a facility should have the 
ability to use at a minimum 12 months of data if the installation of 
technology occurs prior to the compliance date.
    Response: This notice is intended to capture the details agreed 
upon by EPA, Cliffs and ArcelorMittal in a settlement agreement. This 
comment comes from a commenter who was not party to the settlement 
agreement. The detailed compliance schedules contained in the proposed 
FIP are based upon the settlement terms agreed to by Cliffs and 
ArcelorMittal, who operate all of the taconite furnaces subject to this 
FIP. The eight month testing period that was originally proposed was 
considered by them to be of sufficient duration to evaluate the 
performance of their control systems and their effect on pellet 
quality. There is therefore no benefit to extending the testing period 
when such an extension is not necessary. The requirements of BART, and 
not the compliance schedule in this rule, establish the most 
appropriate compliance schedule to be followed by any other taconite 
facility.
    Comment: U.S. Steel supported the provision allowing Tilden to 
exclude emissions data during a natural gas curtailment that is beyond 
a facility's control. These events are typically infrequent, unplanned, 
and may cause the facility to operate in a manner that is not typical.
    Response: EPA appreciates U.S. Steel's support for the provision 
stating that the SO2 limit for Tilden's grate kiln does not 
apply during a natural gas curtailment.

IV. Revision to Equation for Normally Distributed but Not Statistically 
Independent Data

    The proposal describes the process for establishing final emission 
limits to which the identified facilities shall become subject. As 
discussed in the proposal, the final limit must be based on the 95 
percent upper predictive limit (UPL) using CEMS data compiled over an 
eight-month testing period. The UPL is a statistical technique that 
examines an existing set of data points and predicts the chances (i.e., 
the probability) of future data points (in this case, emission rates). 
In general terms, the UPL is a value that is calculated from a data set 
that identifies the emission rate that a source is meeting and would be 
expected to meet a specified percent of the time that the source is 
operating. In this case, the UPL will be the emission rate that the 
taconite facilities are predicted to be below during 95 out of 100 720-
hour averaging periods. The UPL will be based on data obtained during 
an eight-month testing period during which Cliffs and ArcelorMittal are 
primarily focused on operating the controls in a manner that does not 
adversely affect pellet quality, with a wide variability in emissions 
expected. The UPL must be calculated using an equation based on the 
average and variance of a data set, the distribution of the data, the 
quantity of data points, and the compliance period (e.g., a 720-hour 
compliance period).
    The settlement agreement and proposed FIP specified three equations 
for determining the UPL depending upon whether the data are normally 
distributed and, if so, whether the data are statistically independent 
or not statistically independent. In the proposal (the equation numbers 
have been changed in the final), Equation 1 applied to normally 
distributed, statistically independent data sets; Equation 3 applied to 
normally distributed, but not statistically independent data sets; and 
Equation 4, the non-parametric UPL equation, applied to data sets that 
do not conform to a specific distribution. EPA's statistical guidance 
for environmental applications, the ProUCL User Guide,

[[Page 21680]]

includes UPL equations for different types of distributions, as well as 
a non-parametric equation for data sets that do not conform to a 
specific distribution. The guidance does not, however, include an 
equation for normally distributed, but not statistically independent 
(that is, highly correlated) data. Because Cliffs and ArcelorMittal 
were concerned about this latter category of data, we proposed what was 
purported to be an appropriate equation for normally distributed, but 
not statistically independent data (Equation 3). We subsequently found 
that Equation 3 is not valid for large data sets, which is what will 
result from eight months of hourly data. When we applied Equation 3 to 
a large data set, the resulting UPL was higher than the highest 720-
hour average, a nonsensical and mathematically unreasonable result. We 
are therefore eliminating Equation 3 from the final FIP. Instead, we 
are requiring use of the fall back non-parametric equation (Equation 4) 
for data that are normally distributed, but not statistically 
independent.
    We are finalizing the non-parametric equation contained in the 
proposal with a clarification regarding the appropriate data set to be 
used. As stated above, the UPL equations are used to determine emission 
limits. To correctly calculate the UPL using the non-parametric 
equation, the data that is ranked from smallest to highest must be in 
the same form as the emission limit. The final emission limits are 
expressed in terms of 720-hour averages, so the ranked data set used in 
the non-parametric equation must be a set of 720-hour averages as well. 
Using data sets based upon an averaging time inconsistent with the form 
of the emission limit would be an improper use of the equation. For 
instance, calculating the 95 percent non-parametric limit using a data 
set of ranked one-hour values would establish the emission rate (based 
upon a one-hour average) that the source would be predicted to be below 
during 95 out of 100 one-hour averaging periods, i.e., an emission 
limit based on hourly compliance. The resulting emission limit would be 
improper if compliance is to be based upon a 720-hour average. Based 
upon our evaluation of existing data sets, using the 95th percentile of 
the one-hour values to establish a 720-hour average emission limit 
would result in a limit that is higher than the highest 720-hour 
average in the data sets, which is clearly inconsistent with the 
purpose of a 95 percent UPL.
    To reiterate, the purpose of a 95 percent UPL is to establish an 
emission rate that a source is predicted to be below during 95 out of 
100 averaging periods. Importantly, however, this does not mean that 
the source would be expected to exceed its emission limit five percent 
of the time once the limit is in place. During the eight-month testing 
period, Cliffs and ArcelorMittal will operate their furnaces and the 
new control technologies in a manner that will not interfere with 
pellet quality. The furnace operators will be adjusting numerous 
variables to optimize control technology performance, which will result 
in higher emissions at times. These periods of higher emissions will 
factor into the UPL calculation. Once the eight-month testing period is 
over, however, the operators will have gained sufficient experience to 
run the furnaces and control technologies with fewer adjustments, 
meaning less emission variations and lower emissions overall. Using the 
95 percent UPL ensures that the final emission limits will be 
consistent with the actual emission reduction capabilities of the BART 
controls, as required by 40 CFR 51.301, which defines BART as ``the 
degree of reduction achievable.'' We also note that the 720-hour 
averaging period for the final emission limits will provide 
considerable flexibility for the sources. The operators will be able to 
continually review CEMS data on an hourly basis and make any necessary 
adjustments over the remaining 719 hours to ensure compliance.

V. What action is EPA taking?

    For the reasons stated in the proposed FIP revision and the 
response to comments, EPA is finalizing the new BART emission limits 
and related requirements for taconite furnaces as proposed, with two 
exceptions. First, EPA is revising the requirement to report CEMS and 
pellet quality data at the end of a period that did not fall within the 
preceding calendar quarter from within 7 days of the close of the 
period to within 30 days of the close of the period. This revision will 
allow the facilities sufficient time to complete the appropriate 
laboratory analyses and quality assurance for the data and will not 
significantly interfere with expeditiously setting the final limits. 
Second, EPA is replacing the incorrect equation for normally 
distributed but not statistically independent data with the non-
parametric UPL equation, which is consistent with EPA guidance. A 
summary of our final decision is included in the table below.

                            Summary of Final Emission Limits and Compliance Schedules
----------------------------------------------------------------------------------------------------------------
                                          Compliance     NOX limit for   NOX limit for
                Source                     schedule      gas/coal mix   gas only (lbs/       SO[ihel2] limit
                                           (months)       (lbs/MMBtu)       MMBtu)
----------------------------------------------------------------------------------------------------------------
Tilden................................              60         1.5-2.5         2.8-3.0  500 lbs/hr and 0.6%S.
Hibbing 1.............................              37  ..............         1.2-1.8  ........................
Hibbing 2.............................              55  ..............         1.2-1.8  ........................
Hibbing 3.............................              60  ..............         1.2-1.8  ........................
UTAC 1................................              37         1.5-2.5         2.8-3.0  529 lbs/hr (combined
                                                                                         L1&2) and 1.5%S.
UTAC 2................................              55         1.5-2.5         2.8-3.0  529 lbs/hr (combined
                                                                                         L1&2) and 1.5%S.
Minorca Mine..........................              55  ..............         1.2-1.8  ........................
----------------------------------------------------------------------------------------------------------------

VI. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at http://www2.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is exempt from review by the Office of Management and 
Budget (OMB) because it is a rule of particular applicability and only 
affects four facilities.

B. Paperwork Reduction Act (PRA)

    This action does not impose an information collection burden under 
the PRA. Because the FIP applies to just four facilities, the Paperwork 
Reduction Act does not apply. See 5 CFR 1320.3(c).

[[Page 21681]]

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. In 
making this determination, the impact of concern is any significant 
adverse economic impact on small entities. An agency may certify that a 
rule will not have a significant economic impact on a substantial 
number of small entities if the rule relieves regulatory burden, has no 
net burden or otherwise has a positive economic effect on the small 
entities subject to the rule. EPA's rule adds additional controls to 
certain sources. The Regional Haze FIP revisions that EPA is 
promulgating here would impose Federal control requirements to meet the 
BART requirement for NOX and SO2 emissions on 
specific units at three sources in Minnesota and one in Michigan. The 
net result of the FIP action is that EPA is requiring emission controls 
on the indurating furnaces at four taconite furnaces and none of these 
sources are owned by small entities, and therefore are not small 
entities.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. The action imposes no enforceable duty on any state, 
local or tribal governments or the private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

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

    This action does not have tribal implications as specified in 
Executive Order 13175. It will not have substantial direct effects on 
tribal governments. Thus, Executive Order 13175 does not apply to this 
rule. However, EPA did discuss this action on a number of occasions, 
including a June 28, 2015, conference call with the Michigan and 
Minnesota tribes.

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

    This action is not subject to Executive Order 13045 because it is 
not economically significant as defined in Executive Order 12866, and 
because EPA does not believe the environmental health or safety risks 
addressed by this action present a disproportionate risk to children. 
However, to the extent this rule will limit emissions of NOX 
and SO2, the rule will have a beneficial effect on 
children's health by reducing air pollution.

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

    This action is not subject to Executive Order 13211, because it is 
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

    This rulemaking does not involve technical standards.

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

    EPA believes the human health or environmental risk addressed by 
this action will not have potential disproportionately high and adverse 
human health or environmental effects on minority, low-income or 
indigenous populations. We have determined that this rule will not have 
disproportionately high and adverse human health or environmental 
effects on minority or low-income populations because it increases the 
level of environmental protection for all affected populations without 
having any disproportionately high and adverse human health or 
environmental effects on any population, including any minority or low-
income population.

K. Congressional Review Act (CRA)

    This rule is exempt from the CRA because it is a rule of particular 
applicability.

L. Judicial Review

    Under section 307(b)(1) of the CAA, petitions for judicial review 
of this action must be filed in the United States Court of Appeals for 
the appropriate circuit by June 13, 2016. Filing a petition for 
reconsideration by the Administrator of this final rule does not affect 
the finality of this action for the purposes of judicial review nor 
does it extend the time within which a petition for judicial review may 
be filed, and shall not postpone the effectiveness of such rule or 
action. This action may not be challenged later in proceedings to 
enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Particulate 
matter, Reporting and recordkeeping requirements, Sulfur oxides, 
Regional haze, Volatile organic compounds.

    Dated: March 18, 2016.
Gina McCarthy,
Administrator.
    For the reasons stated in the preamble, 40 CFR chapter I is amended 
as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

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

0
2. Section 52.1183 is amended by revising paragraphs (k), (l), (m), and 
(n) and adding paragraph (p) to read as follows:

Sec.  52.1183  Visibility protection.

* * * * *
    (k) Tilden Mining Company, or any subsequent owner/operator of the 
Tilden Mining Company facility in Ishpeming, Michigan, shall meet the 
following requirements:
    (1) NOX Emission Limits. (i) An emission limit of 2.8 lbs 
NOX/MMBTU, based on a 720-hour rolling average, shall apply 
to Tilden Grate Kiln Line 1 when burning natural gas, and an emission 
limit of 1.5 lbs NOX/MMBTU, based on a 720-hour rolling 
average, shall apply to Tilden Grate Kiln Line 1 when burning coal or a 
mixture of coal and natural gas. These emission limits will become 
enforceable 60 months after May 12, 2016 and only after EPA's 
confirmation or modification of the emission limit in accordance with 
the procedures set forth in paragraphs (k)(1)(ii) through (viii) of 
this section.
    (ii) Compliance with these emission limits shall be demonstrated 
with data collected by a continuous emissions monitoring system (CEMS) 
for NOX. The owner or operator must start collecting CEMS 
data for NOX upon May 12, 2016 and submit the data to EPA no 
later than 30 days from the end of each calendar quarter. Any remaining 
data through the end of the 57th month from May 12, 2016, that does not 
fall within a calendar quarter, must be submitted to EPA no later than 
30 days from the end of the 57th month. Although CEMS data must 
continue to be collected, it does

[[Page 21682]]

not need to be submitted to EPA starting 57 months after May 12, 2016.
    (iii) No later than 48 months from May 12, 2016, the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on Tilden Grate Kiln Line 1. This report 
must include a list of all variables that can reasonably be expected to 
have an impact on NOX emission control technology 
performance, as well as a description of how these variables can be 
adjusted to reduce NOX emissions to meet the NOX 
design emission limit. This NOX reduction control technology 
must be designed to meet emission limits of 2.8 lbs NOX/
MMBTU when burning natural gas and 1.5 lbs NOX/MMBTU when 
burning coal or a mixture of coal and natural gas.
    (iv) The NOX reduction control technology shall be 
installed on Tilden Grate Kiln Line 1 furnace no later than 50 months 
from May 12, 2016.
    (v) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology or 50 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 57 months after May 12, 2016. Any 
remaining results through the end of the 57th month that do not fall 
within a calendar quarter must be submitted to EPA no later than 30 
days from the end of the 57th month. The pellet quality analyses shall 
include results for the following factors: Compression, reducibility, 
before tumble, after tumble, and low temperature disintegration. For 
each of the pellet quality analysis factors the owner or operator must 
explain the pellet quality analysis factor as well as the defined 
acceptable range for each factor using the applicable product quality 
standards based upon customers' pellet specifications that are 
contained in Tilden's ISO 9001 quality management system. The owner or 
operator shall provide pellet quality analysis testing results that 
state the date and time of the analysis and, in order to define the 
time period when pellets were produced outside of the defined 
acceptable range for the pellet quality factors listed, provide copies 
of the production logs that document the starting and ending times for 
such periods. The owner or operator shall provide an explanation of 
causes for pellet samples that fail to meet the acceptable range for 
any pellet quality analysis factor. Pellet quality information and data 
may be submitted to EPA as Confidential Business Information.
    (vi) No later than 57 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for Tilden Grate Kiln Line 1 within the upper and 
lower bounds described below. EPA will review the report and either 
confirm or modify the NOX limits. If the CEMS data collected 
during operating periods between months 50 and 57 that both meet pellet 
quality specifications and proper furnace/burner operation is normally 
distributed, the limit adjustment determination shall be based on the 
appropriate (depending upon whether data are statistically independent 
or dependent) 95% upper predictive limit (UPL) equations in paragraph 
(p) of this section. If the CEMS data collected during operating 
periods between months 50 and 57 that both meet pellet quality 
specifications and proper furnace/burner operation are not normally 
distributed, the limit adjustment determination shall be based on the 
non-parametric equation provided in paragraph (p) of this section. The 
data set for the determination shall exclude periods when pellet 
quality did not fall within the defined acceptable ranges of the pellet 
quality factors identified pursuant to paragraph (k)(1)(v) of this 
section and for any subsequent period when production had been reduced 
in response to pellet quality concerns consistent with Tilden's ISO 
9001 operating standards. Any excluded period will commence at the time 
documented on the production log demonstrating pellet quality did not 
fall within the defined acceptable range and shall end when pellet 
quality within the defined acceptable range has been re-established at 
planned production levels, which will be presumed to be the level that 
existed immediately prior to the reduction in production due to pellet 
quality concerns. EPA may also exclude data where operations are 
inconsistent with the reported design parameters of the NOX 
reduction control technology that were installed.
    (vii) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limits in the 
Federal Register no later than 60 months after May 12, 2016. The 
confirmed or modified NOX limit for Tilden Grate Kiln Line 1 
when burning only natural gas may be no lower than 2.8 lbs 
NOX/MMBTU, based on a 720-hour rolling average, and may not 
exceed 3.0 lbs NOX/MMBTU, based on a 720-hour rolling 
average. The confirmed or modified NOX limit for Tilden 
Grate Kiln Line 1 when burning coal or a mixture of coal and natural 
gas may be no lower than 1.5 lbs NOX/MMBTU, based on a 720-
hour rolling average, and may not exceed 2.5 lbs NOX/MMBTU, 
based on a 720-hour rolling average.
    (viii) If the owner or operator submits a report proposing a single 
NOX limit for all fuels, EPA may approve the proposed 
NOX limit for all fuels based on a 30-day rolling average. 
The confirmed or modified limit will be established and enforceable 
within 60 months from May 12, 2016.
    (2) SO2 Emission Limits. A fuel sulfur content limit of no greater 
than 1.20 percent sulfur content by weight shall apply to fuel 
combusted in Process Boiler #1 (EUBOILER1) and Process Boiler #2 
(EUBOILER2) beginning three months from March 8, 2013. A fuel sulfur 
content limit of no greater than 1.50 percent sulfur content by weight 
shall apply to fuel combusted in the Line 1 Dryer (EUDRYER1) beginning 
3 months from March 8, 2013. The sampling and calculation methodology 
for determining the sulfur content of fuel must be described in the 
monitoring plan required at paragraph (n)(8)(x) of this section.
    (3) The owner or operator of the Tilden Grate Kiln Line 1 furnace 
shall meet an emission limit of 500 lbs SO2/hr based on a 
30-day rolling average beginning six months after May 12, 2016. 
Compliance with these emission limits shall be demonstrated with data 
collected by a continuous emissions monitoring system (CEMS) for 
SO2. The owner or operator must start collecting CEMS data 
for SO2 beginning six months after May 12, 2016 and submit 
the data to EPA no later than 30 days from the end of each calendar 
quarter. The Tilden Grate Kiln Line 1 furnace shall not be limited to 
natural gas fuel. Beginning six months after May 12, 2016, any coal 
burned on Tilden Grate Kiln Line 1 shall have no more than 0.60 percent 
sulfur by weight based on a monthly block average. The sampling and 
calculation methodology for determining the sulfur content of coal must 
be described in the monitoring plan required for this furnace. The 
owner or operator must calculate an SO2 limit based on 12 
continuous months of CEMS emissions data and submit such limit, 
calculations, and CEMS data to EPA no later than 36 months after May 
12, 2016. If the submitted CEMS SO2 hourly data are normally 
distributed, the SO2 lbs/hr emission rate shall be

[[Page 21683]]

based on the appropriate (depending upon whether data are statistically 
independent or dependent) 99% upper predictive limit (UPL) equation. If 
the submitted CEMS SO2 hourly data are not normally 
distributed, the SO2 lbs/hr emission rate shall be based on 
the non-parametric equation provided in paragraph (p) of this section. 
Compliance with the SO2 lbs/hr emission rate shall be 
determined on a 30-day rolling average basis. EPA will take final 
agency action by publishing a confirmation or modification of the 
SO2 limit in the Federal Register no later than 39 months 
after May 12, 2016. EPA may adjust the 500 lbs SO2/hr limit 
downward to reflect the calculated SO2 emission rate; 
however, EPA will not increase the SO2 limit above 500 lbs 
SO2/hr.
    (4) Starting 26 months from May 12, 2016, records shall be kept for 
any day during which fuel oil is burned as fuel (either alone or 
blended with other fuels) in Grate Kiln Line 1. These records must 
include, at a minimum, the gallons of fuel oil burned per hour, the 
sulfur content of the fuel oil, and the SO2 emissions in 
pounds per hour.
    (5) Starting 26 months from May 12, 2016, the SO2 limit 
for Grate Kiln Line 1 does not apply for any hour in which it is 
documented that there is a natural gas curtailment beyond Cliffs' 
control necessitating that the supply of natural gas to Tilden's Line 1 
indurating furnace is restricted or eliminated. Records must be kept of 
the cause of the curtailment and duration of such curtailment. During 
such curtailment, the use of backup coal is restricted to coal with no 
greater than 0.60 percent sulfur by weight.
    (l) Testing and monitoring. (1) The owner or operator shall 
install, certify, calibrate, maintain, and operate a CEMS for 
NOX on Tilden Grate Kiln Line 1. Compliance with the 
emission limits for NOX shall be determined using data from 
the CEMS.
    (2) The owner or operator shall install, certify, calibrate, 
maintain, and operate a CEMS for SO2 on Tilden Grate Kiln 
Line 1. Compliance with the emission standard selected for 
SO2 shall be determined using data from the CEMS.
    (3) The owner or operator shall install, certify, calibrate, 
maintain, and operate one or more continuous diluent monitor(s) 
(O2 or CO2) and continuous flow rate monitor(s) 
on Tilden Grate Kiln Line 1 to allow conversion of the NOX 
and SO2 concentrations to units of the standard (lbs/MMBTU 
and lbs/hr, respectively) unless a demonstration is made that a diluent 
monitor and continuous flow rate monitor are not needed for the owner 
or operator to demonstrate compliance with applicable emission limits 
in units of the standards.
    (4) For purposes of this section, all CEMS required by this section 
must meet the requirements of paragraphs (l)(4)(i) through (xiv) of 
this section.
    (i) All CEMS must be installed, certified, calibrated, maintained, 
and operated in accordance with 40 CFR part 60, appendix B, Performance 
Specification 2 (PS-2) and appendix F, Procedure 1.
    (ii) All CEMS associated with monitoring NOX (including 
the NOX monitor and necessary diluent and flow rate 
monitors) must be installed and operational upon May 12, 2016. All CEMS 
associated with monitoring SO2 must be installed and 
operational no later than six months after May 12, 2016. Verification 
of the CEMS operational status shall, as a minimum, include completion 
of the manufacturer's written requirements or recommendations for 
installation, operation, and calibration of the devices.
    (iii) The owner or operator must conduct a performance evaluation 
of each CEMS in accordance with 40 CFR part 60, appendix B, PS-2. The 
performance evaluations must be completed no later than 60 days after 
the respective CEMS installation.
    (iv) The owner or operator of each CEMS must conduct periodic 
Quality Assurance, Quality Control (QA/QC) checks of each CEMS in 
accordance with 40 CFR part 60, appendix F, Procedure 1. The first CEMS 
accuracy test will be a relative accuracy test audit (RATA) and must be 
completed no later than 60 days after the respective CEMS installation.
    (v) The owner or operator of each CEMS must furnish the Regional 
Administrator two, or upon request, more copies of a written report of 
the results of each performance evaluation and QA/QC check within 60 
days of completion.
    (vi) The owner or operator of each CEMS must check, record, and 
quantify the zero and span calibration drifts at least once daily 
(every 24 hours) in accordance with 40 CFR part 60, appendix F, 
Procedure 1, Section 4.
    (vii) Except for CEMS breakdowns, repairs, calibration checks, and 
zero and span adjustments, all CEMS required by this section shall be 
in continuous operation during all periods of process operation of the 
indurating furnaces, including periods of process unit startup, 
shutdown, and malfunction.
    (viii) All CEMS required by this section must meet the minimum data 
requirements at paragraphs (l)(4)(viii)(A) through (C) of this section.
    (A) Complete a minimum of one cycle of operation (sampling, 
analyzing, and data recording) for each successive 15-minute quadrant 
of an hour.
    (B) Sample, analyze, and record emissions data for all periods of 
process operation except as described in paragraph (l)(4)(viii)(C) of 
this section.
    (C) When emission data from CEMS are not available due to 
continuous monitoring system breakdowns, repairs, calibration checks, 
or zero and span adjustments, emission data must be obtained using 
other monitoring systems or emission estimation methods approved by the 
EPA. The other monitoring systems or emission estimation methods to be 
used must be incorporated into the monitoring plan required by this 
section and provide information such that emissions data are available 
for a minimum of 18 hours in each 24-hour period and at least 22 out of 
30 successive unit operating days.
    (ix) Owners or operators of each CEMS required by this section must 
reduce all data to 1-hour averages. Hourly averages shall be computed 
using all valid data obtained within the hour but no less than one data 
point in each 15-minute quadrant of an hour. Notwithstanding this 
requirement, an hourly average may be computed from at least two data 
points separated by a minimum of 15 minutes (where the unit operates 
for more than one quadrant in an hour) if data are unavailable as a 
result of performance of calibration, quality assurance, preventive 
maintenance activities, or backups of data from data acquisition and 
handling systems and recertification events.
    (x) The 30-day rolling average emission rate determined from data 
derived from the CEMS required by this section (in lbs/MMBTU or lbs/hr 
depending on the emission standard selected) must be calculated in 
accordance with paragraphs (l)(4)(x)(A) through (F) of this section.
    (A) Sum the total pounds of the pollutant in question emitted from 
the unit during an operating day and the previous 29 operating days.
    (B) Sum the total heat input to the unit (in MMBTU) or the total 
actual hours of operation (in hours) during an operating day and the 
previous 29 operating days.
    (C) Divide the total number of pounds of the pollutant in question 
emitted during the 30 operating days by the total heat input (or actual 
hours of operation depending on the emission limit selected) during the 
30 operating days.
    (D) For purposes of this calculation, an operating day is any day 
during

[[Page 21684]]

which fuel is combusted in the BART affected unit regardless of whether 
pellets are produced. Actual hours of operation are the total hours a 
unit is firing fuel regardless of whether a complete 24-hour 
operational cycle occurs (i.e., if the furnace is firing fuel for only 
five hours during a 24-hour period, then the actual operating hours for 
that day are five. Similarly, total number of pounds of the pollutant 
in question for that day is determined only from the CEMS data for the 
five hours during which fuel is combusted.)
    (E) If the owner or operator of the CEMS required by this section 
uses an alternative method to determine 30-day rolling averages, that 
method must be described in detail in the monitoring plan required by 
this section. The alternative method will only be applicable if the 
final monitoring plan and the alternative method are approved by EPA.
    (F) A new 30-day rolling average emission rate must be calculated 
for the period ending each new operating day.
    (xi) The 720-hour rolling average emission rate determined from 
data derived from the CEMS required by this section (in lbs/MMBTU) must 
be calculated in accordance with paragraphs (l)(4)(xi)(A) through (C) 
of this section.
    (A) Sum the total pounds of NOX emitted from the unit 
every hour and the previous (not necessarily consecutive) 719 hours for 
which that type of fuel (either natural gas or mixed coal and natural 
gas) was used.
    (B) Sum the total heat input to the unit (in MMBTU) every hour and 
the previous (not necessarily consecutive) 719 hours for which that 
type of fuel (either natural gas or mixed coal and natural gas) was 
used.
    (C) Divide the total number of pounds of NOX emitted 
during the 720 hours, as defined above, by the total heat input during 
the same 720-hour period. This calculation must be done separately for 
each fuel type (either for natural gas or mixed coal and natural gas).
    (xii) Data substitution must not be used for purposes of 
determining compliance under this regulation.
    (xiii) All CEMS data shall be reduced and reported in units of the 
applicable standard.
    (xiv) A Quality Control Program must be developed and implemented 
for all CEMS required by this section in accordance with 40 CFR part 
60, appendix F, Procedure 1, Section 3. The program will include, at a 
minimum, written procedures and operations for calibration checks, 
calibration drift adjustments, preventative maintenance, data 
collection, recording and reporting, accuracy audits/procedures, 
periodic performance evaluations, and a corrective action program for 
malfunctioning CEMS.
    (m) Recordkeeping requirements. (1)(i) Records required by this 
section must be kept in a form suitable and readily available for 
expeditious review.
    (ii) Records required by this section must be kept for a minimum of 
five years following the date of creation.
    (iii) Records must be kept on site for at least two years following 
the date of creation and may be kept offsite, but readily accessible, 
for the remaining three years.
    (2) The owner or operator of the BART affected unit must maintain 
the records identified in paragraphs (m)(2)(i) through (xi) of this 
section.
    (i) A copy of each notification and report developed for and 
submitted to comply with this section including all documentation 
supporting any initial notification or notification of compliance 
status submitted, according to the requirements of this section.
    (ii) Records of the occurrence and duration of each startup, 
shutdown, and malfunction of the BART affected unit, air pollution 
control equipment, and CEMS required by this section.
    (iii) Records of activities taken during each startup, shutdown, 
and malfunction of the BART affected unit, air pollution control 
equipment, and CEMS required by this section.
    (iv) Records of the occurrence and duration of all major 
maintenance conducted on the BART affected unit, air pollution control 
equipment, and CEMS required by this section.
    (v) Records of each excess emission report, including all 
documentation supporting the reports, dates and times when excess 
emissions occurred, investigations into the causes of excess emissions, 
actions taken to minimize or eliminate the excess emissions, and 
preventative measures to avoid the cause of excess emissions from 
occurring again.
    (vi) Records of all CEMS data including, as a minimum, the date, 
location, and time of sampling or measurement, parameters sampled or 
measured, and results.
    (vii) All records associated with quality assurance and quality 
control activities on each CEMS as well as other records required by 40 
CFR part 60, appendix F, Procedure 1 including, but not limited to, the 
quality control program, audit results, and reports submitted as 
required by this section.
    (viii) Records of the NOX emissions during all periods 
of BART affected unit operation, including startup, shutdown, and 
malfunction, in the units of the standard. The owner or operator shall 
convert the monitored data into the appropriate unit of the emission 
limitation using appropriate conversion factors and F-factors. F-
factors used for purposes of this section shall be documented in the 
monitoring plan and developed in accordance with 40 CFR part 60, 
appendix A, Method 19. The owner or operator may use an alternate 
method to calculate the NOX emissions upon written approval 
from EPA.
    (ix) Records of the SO2 emissions or records of the 
removal efficiency (based on CEMS data), depending on the emission 
standard selected, during all periods of operation, including periods 
of startup, shutdown, and malfunction, in the units of the standard.
    (x) Records associated with the CEMS unit including type of CEMS, 
CEMS model number, CEMS serial number, and initial certification of 
each CEMS conducted in accordance with 40 CFR part 60, appendix B, 
Performance Specification 2 must be kept for the life of the CEMS unit.
    (xi) Records of all periods of fuel oil usage as required in 
paragraph (k)(4) of this section.
    (n) Reporting requirements. (1) All requests, reports, submittals, 
notifications, and other communications to the Regional Administrator 
required by this section shall be submitted, unless instructed 
otherwise, to the Air and Radiation Division, U.S. Environmental 
Protection Agency, Region 5 (A-18J) at 77 West Jackson Boulevard, 
Chicago, Illinois 60604. References in this section to the Regional 
Administrator shall mean the EPA Regional Administrator for Region 5.
    (2) The owner or operator of each BART affected unit identified in 
this section and CEMS required by this section must provide to the 
Regional Administrator the written notifications, reports, and plans 
identified at paragraphs (n)(2)(i) through (viii) of this section. If 
acceptable to both the Regional Administrator and the owner or operator 
of each BART affected unit identified in this section and CEMS required 
by this section the owner or operator may provide electronic 
notifications, reports, and plans.
    (i) A notification of the date construction of control devices and 
installation of burners required by this section commences postmarked 
no later than 30 days after the commencement date.
    (ii) A notification of the date the installation of each CEMS 
required by this section commences postmarked no later than 30 days 
after the commencement date.

[[Page 21685]]

    (iii) A notification of the date the construction of control 
devices and installation of burners required by this section is 
complete postmarked no later than 30 days after the completion date.
    (iv) A notification of the date the installation of each CEMS 
required by this section is complete postmarked no later than 30 days 
after the completion date.
    (v) A notification of the date control devices and burners 
installed by this section startup postmarked no later than 30 days 
after the startup date.
    (vi) A notification of the date CEMS required by this section 
postmarked no later than 30 days after the startup date.
    (vii) A notification of the date upon which the initial CEMS 
performance evaluations are planned. This notification must be 
submitted at least 60 days before the performance evaluation is 
scheduled to begin.
    (viii) A notification of initial compliance signed by the 
responsible official, who shall certify its accuracy, attesting to 
whether the source has complied with the requirements of this section, 
including, but not limited to, applicable emission standards, control 
device and burner installations, and CEMS installation and 
certification. This notification must be submitted before the close of 
business on the 60th calendar day following the completion of the 
compliance demonstration and must include, at a minimum, the 
information in paragraphs (n)(2)(viii)(A) through (F) of this section.
    (A) The methods used to determine compliance.
    (B) The results of any CEMS performance evaluations and other 
monitoring procedures or methods that were conducted.
    (C) The methods that will be used for determining continuing 
compliance, including a description of monitoring and reporting 
requirements and test methods.
    (D) The type and quantity of air pollutants emitted by the source, 
reported in units of the standard.
    (E) A description of the air pollution control equipment and 
burners installed as required by this section for each emission point.
    (F) A statement by the owner or operator as to whether the source 
has complied with the relevant standards and other requirements.
    (3) The owner or operator must develop and implement a written 
startup, shutdown, and malfunction plan for NOX and 
SO2. The plan must include, at a minimum, procedures for 
operating and maintaining the source during periods of startup, 
shutdown, and malfunction and a program of corrective action for a 
malfunctioning process and air pollution control and monitoring 
equipment used to comply with the relevant standard. The plan must 
ensure that, at all times, the owner or operator operates and maintains 
each affected source, including associated air pollution control and 
monitoring equipment, in a manner which satisfies the general duty to 
minimize or eliminate emissions using good air pollution control 
practices. The plan must ensure that owners or operators are prepared 
to correct malfunctions as soon as practicable after their occurrence.
    (4) The written reports of the results of each performance 
evaluation and QA/QC check in accordance with and as required in 
paragraph (l)(4)(v) of this section.
    (5) Compliance reports. The owner or operator of each BART affected 
unit must submit semiannual compliance reports. The semiannual 
compliance reports must be submitted in accordance with paragraphs 
(n)(5)(i) through (iv) of this section, unless the Regional 
Administrator has approved a different schedule.
    (i) The first compliance report must cover the period beginning on 
the compliance date that is specified for the affected source through 
June 30 or December 31, whichever date comes first after the compliance 
date that is specified for the affected source.
    (ii) The first compliance report must be postmarked no later than 
30 calendar days after the reporting period covered by that report 
(July 30 or January 30), whichever comes first.
    (iii) Each subsequent compliance report must cover the semiannual 
reporting period from January 1 through June 30 or the semiannual 
reporting period from July 1 through December 31.
    (iv) Each subsequent compliance report must be postmarked no later 
than 30 calendar days after the reporting period covered by that report 
(July 30 or January 30).
    (6) Compliance report contents. Each compliance report must include 
the information in paragraphs (n)(6)(i) through (vi) of this section.
    (i) Company name and address.
    (ii) Statement by a responsible official, with the official's name, 
title, and signature, certifying the truth, accuracy, and completeness 
of the content of the report.
    (iii) Date of report and beginning and ending dates of the 
reporting period.
    (iv) Identification of the process unit, control devices, and CEMS 
covered by the compliance report.
    (v) A record of each period of a startup, shutdown, or malfunction 
during the reporting period and a description of the actions the owner 
or operator took to minimize or eliminate emissions arising as a result 
of the startup, shutdown, or malfunction and whether those actions were 
or were not consistent with the source's startup, shutdown, and 
malfunction plan.
    (vi) A statement identifying whether there were or were not any 
deviations from the requirements of this section during the reporting 
period. If there were deviations from the requirements of this section 
during the reporting period, then the compliance report must describe 
in detail the deviations which occurred, the causes of the deviations, 
actions taken to address the deviations, and procedures put in place to 
avoid such deviations in the future. If there were no deviations from 
the requirements of this section during the reporting period, then the 
compliance report must include a statement that there were no 
deviations. For purposes of this section, deviations include, but are 
not limited to, emissions in excess of applicable emission standards 
established by this section, failure to continuously operate an air 
pollution control device in accordance with operating requirements 
designed to assure compliance with emission standards, failure to 
continuously operate CEMS required by this section, and failure to 
maintain records or submit reports required by this section.
    (7) Each owner or operator of a CEMS required by this section must 
submit quarterly excess emissions and monitoring system performance 
reports to the Regional Administrator for each pollutant monitored for 
each BART affected unit monitored. All reports must be postmarked by 
the 30th day following the end of each 3-month period of a calendar 
year (January-March, April-June, July-September, October-December) and 
must include, at a minimum, the requirements of paragraphs (n)(7)(i) 
through (xv) of this section.
    (i) Company name and address.
    (ii) Identification and description of the process unit being 
monitored.
    (iii) The dates covered by the reporting period.
    (iv) Total source operating hours for the reporting period.
    (v) Monitor manufacturer, monitor model number, and monitor serial 
number.
    (vi) Pollutant monitored.
    (vii) Emission limitation for the monitored pollutant.
    (viii) Date of latest CEMS certification or audit.

[[Page 21686]]

    (ix) A description of any changes in continuous monitoring systems, 
processes, or controls since the last reporting period.
    (x) A table summarizing the total duration of excess emissions, as 
defined in paragraphs (n)(7)(x)(A) through (B) of this section, for the 
reporting period broken down by the cause of those excess emissions 
(startup/shutdown, control equipment problems, process problems, other 
known causes, unknown causes), and the total percent of excess 
emissions (for all causes) for the reporting period calculated as 
described in paragraph (n)(7)(x)(C) of this section.
    (A) For purposes of this section, an excess emission is defined as 
any 30-day or 720-hour rolling average period, including periods of 
startup, shutdown, and malfunction, during which the 30-day or 720-hour 
(as appropriate) rolling average emissions of either regulated 
pollutant (SO2 and NOX), as measured by a CEMS, 
exceeds the applicable emission standards in this section.
    (B)(1) For purposes of this section, if a facility calculates a 30-
day rolling average emission rate in accordance with this section which 
exceeds the applicable emission standards of this section, then it will 
be considered 30 days of excess emissions. If the following 30-day 
rolling average emission rate is calculated and found to exceed the 
applicable emission standards of this section as well, then it will add 
one more day to the total days of excess emissions (i.e. 31 days). 
Similarly, if an excess emission is calculated for a 30-day rolling 
average period and no additional excess emissions are calculated until 
15 days after the first, then that new excess emission will add 15 days 
to the total days of excess emissions (i.e. 30 + 15 = 45). For purposes 
of this section, if an excess emission is calculated for any period of 
time within a reporting period, there will be no fewer than 30 days of 
excess emissions but there should be no more than 121 days of excess 
emissions for a reporting period.
    (2) For purposes of this section, if a facility calculates a 720-
hour rolling average emission rate in accordance with this section 
which exceeds the applicable emission standards of this section, then 
it will be considered 30 days of excess emissions. If the 24th 
following 720-hour rolling average emission rate is calculated and 
found to exceed the applicable emission standards of the rule as well, 
then it will add one more day to the total days of excess emissions 
(i.e. 31 days). Similarly, if an excess emission is calculated for a 
720-hour rolling average period and no additional excess emissions are 
calculated until 360 hours after the first, then that new excess 
emission will add 15 days to the total days of excess emissions (i.e. 
30+15 = 45). For purposes of this section, if an excess emission is 
calculated for any period of time with a reporting period, there will 
be no fewer than 30 days of excess emissions but there should be no 
more than 121 days of excess emissions for a reporting period.
    (C) For purposes of this section, the total percent of excess 
emissions will be determined by summing all periods of excess emissions 
(in days) for the reporting period, dividing that number by the total 
BART affected unit operating days for the reporting period, and then 
multiplying by 100 to get the total percent of excess emissions for the 
reporting period. An operating day, as defined previously, is any day 
during which fuel is fired in the BART affected unit for any period of 
time. Because of the possible overlap of 30-day rolling average excess 
emissions across quarters, there are some situations where the total 
percent of excess emissions could exceed 100 percent. This extreme 
situation would only result from serious excess emissions problems 
where excess emissions occur for nearly every day during a reporting 
period.
    (xi) A table summarizing the total duration of monitor downtime, as 
defined in paragraph (n)(7)(xi)(A) of this section, for the reporting 
period broken down by the cause of the monitor downtime (monitor 
equipment malfunctions, non-monitor equipment malfunctions, quality 
assurance calibration, other known causes, unknown causes), and the 
total percent of monitor downtime (for all causes) for the reporting 
period calculated as described in paragraph (n)(7)(xi)(B) of this 
section.
    (A) For purposes of this section, monitor downtime is defined as 
any period of time (in hours) during which the required monitoring 
system was not measuring emissions from the BART affected unit. This 
includes any period of CEMS QA/QC, daily zero and span checks, and 
similar activities.
    (B) For purposes of this section, the total percent of monitor 
downtime will be determined by summing all periods of monitor downtime 
(in hours) for the reporting period, dividing that number by the total 
number of BART affected unit operating hours for the reporting period, 
and then multiplying by 100 to get the total percent of excess 
emissions for the reporting period.
    (xii) A table which identifies each period of excess emissions for 
the reporting period and includes, at a minimum, the information in 
paragraphs (n)(7)(xii)(A) through (F) of this section.
    (A) The date of each excess emission.
    (B) The beginning and end time of each excess emission.
    (C) The pollutant for which an excess emission occurred.
    (D) The magnitude of the excess emission.
    (E) The cause of the excess emission.
    (F) The corrective action taken or preventative measures adopted to 
minimize or eliminate the excess emissions and prevent such excess 
emission from occurring again.
    (xiii) A table which identifies each period of monitor downtime for 
the reporting period and includes, at a minimum, the information in 
paragraphs (n)(7)(xiii)(A) through (D) of this section.
    (A) The date of each period of monitor downtime.
    (B) The beginning and end time of each period of monitor downtime.
    (C) The cause of the period of monitor downtime.
    (D) The corrective action taken or preventative measures adopted 
for system repairs or adjustments to minimize or eliminate monitor 
downtime and prevent such downtime from occurring again.
    (xiv) If there were no periods of excess emissions during the 
reporting period, then the excess emission report must include a 
statement which says there were no periods of excess emissions during 
this reporting period.
    (xv) If there were no periods of monitor downtime, except for daily 
zero and span checks, during the reporting period, then the excess 
emission report must include a statement which says there were no 
periods of monitor downtime during this reporting period except for the 
daily zero and span checks.
    (8) The owner or operator of each CEMS required by this section 
must develop and submit for review and approval by the Regional 
Administrator a site specific monitoring plan. The purpose of this 
monitoring plan is to establish procedures and practices which will be 
implemented by the owner or operator in its effort to comply with the 
monitoring, recordkeeping, and reporting requirements of this section. 
The monitoring plan must include, at a minimum, the information in 
paragraphs (n)(8)(i) through (x) of this section.
    (i) Site specific information including the company name, address, 
and contact information.
    (ii) The objectives of the monitoring program implemented and 
information

[[Page 21687]]

describing how those objectives will be met.
    (iii) Information on any emission factors used in conjunction with 
the CEMS required by this section to calculate emission rates and a 
description of how those emission factors were determined.
    (iv) A description of methods to be used to calculate emission 
rates when CEMS data are not available due to downtime associated with 
QA/QC events.
    (v) A description of the QA/QC program to be implemented by the 
owner or operator of CEMS required by this section. This can be the QA/
QC program developed in accordance with 40 CFR part 60, appendix F, 
Procedure 1, Section 3.
    (vi) A list of spare parts for CEMS maintained on site for system 
maintenance and repairs.
    (vii) A description of the procedures to be used to calculate 30-
day rolling averages and 720-hour rolling averages and example 
calculations which show the algorithms used by the CEMS to calculate 
30-day rolling averages and 720-hour rolling averages.
    (viii) A sample of the document to be used for the quarterly excess 
emission reports required by this section.
    (ix) A description of the procedures to be implemented to 
investigate root causes of excess emissions and monitor downtime and 
the proposed corrective actions to address potential root causes of 
excess emissions and monitor downtime.
    (x) A description of the sampling and calculation methodology for 
determining the percent sulfur by weight as a monthly block average for 
coal used during that month.
    (p) Equations for establishing the upper predictive limit--(1) 
Equation for normal distribution and statistically independent data.
[GRAPHIC] [TIFF OMITTED] TR12AP16.000

Where:

x = average or mean of hourly test run data;
t[(n-1),(0.95)] = t score, the one-tailed t 
value of the Student's t distribution for a specific degree of 
freedom (n-1) and a confidence level (0.95; 0.99 for Tilden 
SO2)
s\2\ = variance of the hourly data set;
n = number of values (e.g. 5,760 if 8 months of valid lbs 
NOX/MMBTU hourly values)
m = number of values used to calculate the test average (m = 720 as 
per averaging time)

    (i) To determine if statistically independent, use the Rank von 
Neumann Test on p. 137 of data Quality Assessment: Statistical Methods 
for Practitioners EPA QA/G-9S.
    (ii) Alternative to Rank von Neumann test to determine if data are 
dependent, data are dependent if t test value is greater than t 
critical value, where:
[GRAPHIC] [TIFF OMITTED] TR12AP16.001

[rho] = correlation between data points
t critical = t[(n-2),(0.95)] = t score, the 
two-tailed t value of the Student's t distribution for a specific 
degree of freedom (n-2) and a confidence level (0.95)

    (iii) The Anderson-Darling normality test is used to establish 
whether the data are normally distributed. That is, a distribution is 
considered to be normally distributed when p > 0.05.
    (2) Non-parametric equation for data not normally distributed and 
normally distributed but not statistically independent.

m = (n + 1) * [alpha]

m = the rank of the ordered data point, when data are sorted 
smallest to largest. The data points are 720-hour averages for 
establishing NOX limits.
n = number of data points (e.g., 5040 720-hourly averages for eight 
months of valid NOX lbs/MMBTU values)
[alpha] = 0.95, to reflect the 95th percentile

    If m is a whole number, then the limit, UPL, shall be computed as:

UPL = Xm

Where:

Xm = value of the m\th\ data point in terms of lbs SO2/hr 
or lbs NOX/MMBTU, when the data are sorted smallest to 
largest.

    If m is not a whole number, the limit shall be computed by linear 
interpolation according to the following equation.

UPL = xm = xmi[middot]md = xmi + 0.md (xmi+1-xmi)

Where:

mi = the integer portion of m, i.e., m truncated at zero decimal 
places, and
md = the decimal portion of m

0
3. Section 52.1235 is amended by revising paragraphs (b)(1)(ii), 
(b)(1)(iv), (b)(1)(v), (b)(2)(iv), (c), (d), and (e) and by adding 
paragraph (f) to read as follows:

Sec.  52.1235  Regional haze.

* * * * *
    (b)
    (1) * * *
    (ii) Hibbing Taconite Company--(A) Hibbing Line 1. (1) An emission 
limit of 1.2 lbs NOX/MMBTU, based on a 30-day rolling 
average, shall apply to Hibbing Line 1 when burning natural gas. This 
emission limit will become enforceable 37 months after May 12, 2016 and 
only after EPA's confirmation or modification of the emission limit in 
accordance with the procedures set forth in paragraphs (b)(1)(ii)(A)(2) 
through (7) of this section.
    (2) Compliance with this emission limit will be demonstrated with 
data collected by a continuous emissions monitoring system (CEMS) for 
NOX. The owner or operator of Hibbing Line 1 must install a 
CEMS for NOX and SO2 within six months from May 
12, 2016. The owner or operator must start collecting CEMS data and 
submit the data to EPA no later than 30 days from the end of each 
calendar quarter after that installation deadline. Any remaining data 
through the end of the 34th month from May 12, 2016, that does not fall 
within a calendar quarter, must be submitted to EPA no later than 30 
days from the end of the 34th month. Although CEMS data must continue 
to be collected, it does not need to be submitted to EPA starting 34 
months after May 12, 2016.
    (3) No later than 24 months after May 12, 2016 the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on Hibbing Line 1. The NOX 
reduction control technology must be designed to meet an emission limit 
of 1.2 lbs NOX/MMBTU. This report must include a list of all 
process and control technology variables that can reasonably be 
expected to have an impact on NOX emissions control 
technology performance, as well as a description of how these variables 
can be adjusted to reduce NOX emissions to meet the 
NOX design emission limit.
    (4) The NOX reduction control technology shall be 
installed on Hibbing Line 1 furnace no later than 26 months after May 
12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology; or 26 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 34 months after May 12, 2016. Any 
remaining results through the end of the 34th month from May 12, 2016, 
that do not fall within a calendar quarter, must be submitted to EPA no 
later than 30 days from the end of the 34th month. The

[[Page 21688]]

pellet quality analyses shall include results for the following 
factors: Compression, reducibility, before tumble, after tumble, low 
temperature disintegration, and swelling. For each of the pellet 
quality analysis factors, the owner or operator must explain the pellet 
quality analysis factor, as well as the defined acceptable range for 
each factor using the applicable product quality standards based upon 
customers' pellet specifications that are contained in Hibbing's ISO 
9001 quality management system. The owner or operator shall provide 
pellet quality analysis testing results that state the date and time of 
the analysis and, in order to define the time period when pellets were 
produced outside of the defined acceptable range for the pellet quality 
factors listed, provide copies of the production logs that document the 
starting and ending times for such periods. The owner or operator shall 
provide an explanation of causes for pellet samples that fail to meet 
the acceptable range for any pellet quality analysis factor. Pellet 
quality information and data may be submitted to EPA as Confidential 
Business Information.
    (6) No later than 34 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for Hibbing Line 1 furnace within the upper and 
lower bounds described below. EPA will review the report and either 
confirm or modify the NOX limits. If the CEMS data collected 
during operating periods between months 26 and 34 that both meet pellet 
quality specifications and proper furnace/burner operation is normally 
distributed, the limit adjustment determination shall be based on the 
appropriate (depending upon whether data are statistically independent 
or dependent) 95% upper predictive limit (UPL) equations in paragraph 
(f) of this section. If the CEMS data collected during operating 
periods between months 26 and 34 that both meet pellet quality 
specifications and proper furnace/burner operation are not normally 
distributed, the limit adjustment determination shall be based on the 
non-parametric equation provided in paragraph (f) of this section. The 
data set for the determination shall exclude periods when pellet 
quality did not fall within the defined acceptable ranges of the pellet 
quality factors identified pursuant to paragraph (b)(1)(ii)(E) of this 
section and for any subsequent period when production has been reduced 
in response to pellet quality concerns consistent with Hibbing's ISO 
9001 operating standards. Any excluded period will commence at the time 
documented on the production log demonstrating that pellet quality did 
not fall within the defined acceptable range and shall end when pellet 
quality within the defined acceptable range has been re-established at 
planned production levels, which will be presumed to be the level that 
existed immediately prior to the reduction in production due to pellet 
quality concerns. EPA may also exclude data where operations are 
inconsistent with the reported design parameters of the NOX 
reduction control technology installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limit in the Federal 
Register no later than 37 months after May 12, 2016. The confirmed or 
modified NOX limit for Hibbing Line 1 when burning only 
natural gas may be no lower than 1.2 lbs NOX/MMBTU, based on 
a 30-day rolling average, and may not exceed 1.8 lbs NOX/
MMBTU, based on a 30-day rolling average.
    (B) Hibbing Line 2. (1) An emission limit of 1.2 lbs 
NOX/MMBTU, based on a 30-day rolling average, shall apply to 
Hibbing Line 2 when burning natural gas. This emission limit will 
become enforceable 55 months after May 12, 2016 and only after EPA's 
confirmation or modification of the emission limit in accordance with 
the procedures set forth in paragraphs (b)(1)(ii)(B)(2) through (7) of 
this section.
    (2) Compliance with this emission limit will be demonstrated with 
data collected by a continuous emissions monitoring system (CEMS) for 
NOX. The owner or operator of Hibbing Line 2 must install a 
CEMS for NOX and SO2 within six months from May 
12, 2016. The owner or operator must start collecting CEMS data and 
submit the data to EPA no later than 30 days from the end of each 
calendar quarter after that installation deadline. Any remaining data 
through the end of the 52nd month from May 12, 2016, that does not fall 
within a calendar quarter, must be submitted to EPA no later than 30 
days from the end of the 52nd month. Although CEMS data must continue 
to be collected, it does not need to be submitted to EPA starting 52 
months after May 12, 2016.
    (3) No later than 42 months after May 12, 2016 the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on Hibbing Line 2. The NOX 
reduction control technology must be designed to meet an emission limit 
of 1.2 lbs NOX/MMBTU. This report must include a list of all 
process and control technology variables that can reasonably be 
expected to have an impact on NOX emissions control 
technology performance, as well as a description of how these variables 
can be adjusted to reduce NOX emissions to meet the 
NOX design emission limit.
    (4) The NOX reduction control technology shall be 
installed on Hibbing Line 2 furnace no later than 44 months after May 
12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology; or 44 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 52 months after May 12, 2016. Any 
remaining results through the end of the 52nd month from May 12, 2016, 
that do not fall within a calendar quarter, must be submitted to EPA no 
later than 30 days from the end of the 52nd month. The pellet quality 
analyses shall include results for the following factors: Compression, 
reducibility, before tumble, after tumble, low temperature 
disintegration, and swelling. For each of the pellet quality analysis 
factors, the owner or operator must explain the pellet quality analysis 
factor, as well as the defined acceptable range for each factor using 
the applicable product quality standards based upon customers' pellet 
specifications that are contained in Hibbing's ISO 9001 quality 
management system. The owner or operator shall provide pellet quality 
analysis testing results that state the date and time of the analysis 
and, in order to define the time period when pellets were produced 
outside of the defined acceptable range for the pellet quality factors 
listed, provide copies of the production logs that document the 
starting and ending times for such periods. The owner or operator shall 
provide an explanation of causes for pellet samples that fail to meet 
the acceptable range for any pellet quality analysis factor. Pellet 
quality information and data may be submitted to EPA as Confidential 
Business Information.
    (6) No later than 52 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for Hibbing Line 2 furnace within the upper and 
lower bounds described below. EPA

[[Page 21689]]

will review the report and either confirm or modify the NOX 
limits. If the CEMS data collected during operating periods between 
months 44 and 52 that both meet pellet quality specifications and 
proper furnace/burner operation is normally distributed, the limit 
adjustment determination shall be based on the appropriate (depending 
upon whether data are statistically independent or dependent) 95% upper 
predictive limit (UPL) equations in paragraph (f) of this section. If 
the CEMS data collected during operating periods between months 44 and 
52 that both meet pellet quality specifications and proper furnace/
burner operation are not normally distributed, the limit adjustment 
determination shall be based on the non-parametric equation provided in 
paragraph (f) of this section. The data set for the determination shall 
exclude periods when pellet quality did not fall within the defined 
acceptable ranges of the pellet quality factors identified pursuant to 
paragraph (b)(1)(ii)(E) of this section and for any subsequent period 
when production has been reduced in response to pellet quality concerns 
consistent with Hibbing's ISO 9001 operating standards. Any excluded 
period will commence at the time documented on the production log 
demonstrating that pellet quality did not fall within the defined 
acceptable range and shall end when pellet quality within the defined 
acceptable range has been re-established at planned production levels, 
which will be presumed to be the level that existed immediately prior 
to the reduction in production due to pellet quality concerns. EPA may 
also exclude data where operations are inconsistent with the reported 
design parameters of the NOX reduction control technology 
installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limit in the Federal 
Register no later than 55 months after May 12, 2016. The confirmed or 
modified NOX limit for Hibbing Line 2 when burning only 
natural gas may be no lower than 1.2 lbs NOX/MMBTU, based on 
a 30-day rolling average, and may not exceed 1.8 lbs NOX/
MMBTU, based on a 30-day rolling average.
    (C) Hibbing Line 3. (1) An emission limit of 1.2 lbs 
NOX/MMBTU, based on a 30-day rolling average, shall apply to 
Hibbing Line 3 when burning natural gas. This emission limit will 
become enforceable 60 months after May 12, 2016 and only after EPA's 
confirmation or modification of the emission limit in accordance with 
the procedures set forth in paragraphs (b)(1)(ii)(C)(2) through (7) of 
this section.
    (2) Compliance with this emission limit will be demonstrated with 
data collected by a continuous emissions monitoring system (CEMS) for 
NOX. The owner or operator of Hibbing Line 3 must install a 
CEMS for NOX and SO2 within six months from May 
12, 2016. The owner or operator must start collecting CEMS data and 
submit the data to EPA no later than 30 days from the end of each 
calendar quarter after that installation deadline. Any remaining data 
through the end of the 57th month from May 12, 2016, that does not fall 
within a calendar quarter, must be submitted to EPA no later than 30 
days from the end of the 57th month. Although CEMS data must continue 
to be collected, it does not need to be submitted to EPA starting 57 
months after May 12, 2016.
    (3) No later than 48 months after May 12, 2016 the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on Hibbing Line 3. The NOX 
reduction control technology must be designed to meet an emission limit 
of 1.2 lbs NOX/MMBTU. This report must include a list of all 
process and control technology variables that can reasonably be 
expected to have an impact on NOX emissions control 
technology performance, as well as a description of how these variables 
can be adjusted to reduce NOX emissions to meet the 
NOX design emission limit.
    (4) The NOX reduction control technology shall be 
installed on Hibbing Line 3 furnace no later than 50 months after May 
12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology; or 50 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 57 months after May 12, 2016. Any 
remaining results through the end of the 57th month from May 12, 2016, 
that do not fall within a calendar quarter, must be submitted to EPA no 
later than 30 days from the end of the 57th month. The pellet quality 
analyses shall include results for the following factors: Compression, 
reducibility, before tumble, after tumble, low temperature 
disintegration, and swelling. For each of the pellet quality analysis 
factors, the owner or operator must explain the pellet quality analysis 
factor, as well as the defined acceptable range for each factor using 
the applicable product quality standards based upon customers' pellet 
specifications that are contained in Hibbing's ISO 9001 quality 
management system. The owner or operator shall provide pellet quality 
analysis testing results that state the date and time of the analysis 
and, in order to define the time period when pellets were produced 
outside of the defined acceptable range for the pellet quality factors 
listed, provide copies of the production logs that document the 
starting and ending times for such periods. The owner or operator shall 
provide an explanation of causes for pellet samples that fail to meet 
the acceptable range for any pellet quality analysis factor. Pellet 
quality information and data may be submitted to EPA as Confidential 
Business Information.
    (6) No later than 57 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for Hibbing Line 3 furnace within the upper and 
lower bounds described below. EPA will review the report and either 
confirm or modify the NOX limits. If the CEMS data collected 
during operating periods between months 50 and 57 that both meet pellet 
quality specifications and proper furnace/burner operation is normally 
distributed, the limit adjustment determination shall be based on the 
appropriate (depending upon whether data are statistically independent 
or dependent) 95% upper predictive limit (UPL) equations in paragraph 
(f) of this section. If the CEMS data collected during operating 
periods between months 50 and 57 that both meet pellet quality 
specifications and proper furnace/burner operation are not normally 
distributed, the limit adjustment determination shall be based on the 
non-parametric equation provided in paragraph (f) of this section. The 
data set for the determination shall exclude periods when pellet 
quality did not fall within the defined acceptable ranges of the pellet 
quality factors identified pursuant to paragraph (b)(1)(ii)(E) of this 
section and for any subsequent period when production has been reduced 
in response to pellet quality concerns consistent with Hibbing's ISO 
9001 operating standards. Any excluded period will commence at the time 
documented on the production log demonstrating that pellet quality did 
not fall within the defined acceptable range and shall end when pellet 
quality

[[Page 21690]]

within the defined acceptable range has been re-established at planned 
production levels, which will be presumed to be the level that existed 
immediately prior to the reduction in production due to pellet quality 
concerns. EPA may also exclude data where operations are inconsistent 
with the reported design parameters of the NOX reduction 
control technology installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limit in the Federal 
Register no later than 60 months after May 12, 2016. The confirmed or 
modified NOX limit for Hibbing Line 3 when burning only 
natural gas may be no lower than 1.2 lbs NOX/MMBTU, based on 
a 30-day rolling average, and may not exceed 1.8 lbs NOX/
MMBTU, based on a 30-day rolling average.
* * * * *
    (iv) United Taconite--(A) United Taconite Line 1. (1) An emission 
limit of 2.8 lbs NOX/MMBTU, based on a 720-hour rolling 
average, shall apply to United Taconite Grate Kiln Line 1 when burning 
natural gas, and an emission limit of 1.5 lbs NOX/MMBTU, 
based on a 720-hour rolling average, shall apply to United Taconite 
Grate Kiln Line 1 when burning coal or a mixture of coal and natural 
gas. These emission limits will become enforceable 37 months after May 
12, 2016 and only after EPA's confirmation or modification of the 
emission limit in accordance with the procedures set forth in 
paragraphs (b)(1)(iv)(A)(2) through (8) of this section.
    (2) Compliance with these emission limits shall be demonstrated 
with data collected by a continuous emissions monitoring system (CEMS) 
for NOX. The owner or operator must start collecting CEMS 
data for NOX on May 12, 2016 and submit the data to EPA no 
later than 30 days from the end of each calendar quarter. Any remaining 
data through the end of the 34th month from May 12, 2016, that does not 
fall within a calendar quarter, must be submitted to EPA no later than 
30 days from the end of the 34th month. Although CEMS data must 
continue to be collected, it does not need to be submitted to EPA 
starting 34 months after May 12, 2016.
    (3) No later than 24 months from May 12, 2016, the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on United Taconite Grate Kiln Line 1. This 
report must include a list of all variables that can reasonably be 
expected to have an impact on NOX emission control 
technology performance, as well as a description of how these variables 
can be adjusted to reduce NOX emissions to meet the 
NOX design emission limit. This NOX reduction 
control technology must be designed to meet emission limits of 2.8 lbs 
NOX/MMBTU when burning natural gas and 1.5 lbs 
NOX/MMBTU when burning coal or a mixture of coal and natural 
gas.
    (4) The NOX reduction control technology shall be 
installed on United Taconite Grate Kiln Line 1 furnace no later than 26 
months from May 12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology or 26 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 34 months after May 12, 2016. Any 
remaining results through the end of the 34th month, that do not fall 
within a calendar quarter, must be submitted to EPA no later than 30 
days from the end of the 34th month. The pellet quality analyses shall 
include results for the following factors: Compression, reducibility, 
before tumble, after tumble, and low temperature disintegration. For 
each of the pellet quality analysis factors, the owner or operator must 
explain the pellet quality analysis factor, as well as the defined 
acceptable range for each factor using the applicable product quality 
standards based upon customers' pellet specifications that are 
contained in United Taconite's ISO 9001 quality management system. The 
owner or operator shall provide pellet quality analysis testing results 
that state the date and time of the analysis and, in order to define 
the time period when pellets were produced outside of the defined 
acceptable range for the pellet quality factors listed, provide copies 
of the production logs that document the starting and ending times for 
such periods. The owner or operator shall provide an explanation of 
causes for pellet samples that fail to meet the acceptable range for 
any pellet quality analysis factor. Pellet quality information and data 
may be submitted to EPA as Confidential Business Information.
    (6) No later than 34 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for United Taconite Grate Kiln Line 1 within the 
upper and lower bounds described below. EPA will review the report and 
either confirm or modify the NOX limits. If the CEMS data 
collected during operating periods between months 26 and 34 that both 
meet pellet quality specifications and proper furnace/burner operation 
is normally distributed, the limit adjustment determination shall be 
based on the appropriate (depending upon whether data are statistically 
independent or dependent) 95% upper predictive limit (UPL) equations in 
paragraph (f) of this section. If the CEMS data collected during 
operating periods between months 26 and 34 that both meet pellet 
quality specifications and proper furnace/burner operation are not 
normally distributed, the limit adjustment determination shall be based 
on the non-parametric equation provided in paragraph (f) of this 
section. The data set for the determination shall exclude periods when 
pellet quality did not fall within the defined acceptable ranges of the 
pellet quality factors identified pursuant to paragraph 
(b)(1)(iv)(A)(5) of this section and for any subsequent period when 
production had been reduced in response to pellet quality concerns 
consistent with United Taconite's ISO 9001 operating standards. Any 
excluded period will commence at the time documented on the production 
log demonstrating pellet quality did not fall within the defined 
acceptable range, and shall end when pellet quality within the defined 
acceptable range has been re-established at planned production levels, 
which will be presumed to be the level that existed immediately prior 
to the reduction in production due to pellet quality concerns. EPA may 
also exclude data where operations are inconsistent with the reported 
design parameters of the NOX reduction control technology 
that were installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limits in the 
Federal Register no later than 37 months after May 12, 2016. The 
confirmed or modified NOX limit for United Taconite Grate 
Kiln Line 1 when burning only natural gas may be no lower than 2.8 lbs 
NOX/MMBTU, based on a 720-hour rolling average, and may not 
exceed 3.0 lbs NOX/MMBTU, based on a 720-hour rolling 
average. The confirmed or modified NOX limit for United 
Taconite Grate Kiln Line 1 when burning coal or a mixture of coal and 
natural gas may be no lower than 1.5 lbs NOX/MMBTU, based on 
a 720-hour rolling average, and may not exceed 2.5

[[Page 21691]]

lbs NOX/MMBTU, based on a 720-hour rolling average.
    (8) If the owner or operator submits a report proposing a single 
NOX limit for all fuels, EPA may approve the proposed 
NOX limit for all fuels based on a 30-day rolling average. 
The confirmed or modified limit will be established and enforceable 
within 37 months from May 12, 2016.
    (B) United Taconite Line 2. (1) An emission limit of 2.8 lbs 
NOX/MMBTU, based on a 720-hour rolling average, shall apply 
to United Taconite Grate Kiln Line 2 when burning natural gas, and an 
emission limit of 1.5 lbs NOX/MMBTU, based on a 720-hour 
rolling average, shall apply to United Taconite Grate Kiln Line 2 when 
burning coal or a mixture of coal and natural gas. These emission 
limits will become enforceable 55 months after May 12, 2016 and only 
after EPA's confirmation or modification of the emission limit in 
accordance with the procedures set forth in paragraphs (b)(1)(iv)(B)(2) 
through (8) of this section.
    (2) Compliance with these emission limits shall be demonstrated 
with data collected by a continuous emissions monitoring system (CEMS) 
for NOX. The owner or operator must start collecting CEMS 
data for NOX on May 12, 2016 and submit the data to EPA no 
later than 30 days from the end of each calendar quarter. Any remaining 
data through the end of the 52nd month from May 12, 2016, that does not 
fall within a calendar quarter, must be submitted to EPA no later than 
30 days from the end of the 52nd month. Although CEMS data must 
continue to be collected, it does not need to be submitted to EPA 
starting 52 months after May 12, 2016.
    (3) No later than 42 months from May 12, 2016, the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on United Taconite Grate Kiln Line 2. This 
report must include a list of all variables that can reasonably be 
expected to have an impact on NOX emission control 
technology performance, as well as a description of how these variables 
can be adjusted to reduce NOX emissions to meet the 
NOX design emission limit. This NOX reduction 
control technology must be designed to meet emission limits of 2.8 lbs 
NOX/MMBTU when burning natural gas and 1.5 lbs 
NOX/MMBTU when burning coal or a mixture of coal and natural 
gas.
    (4) The NOX reduction control technology shall be 
installed on United Taconite Grate Kiln Line 2 furnace no later than 44 
months from May 12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology or 44 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 52 months after May 12, 2016. Any 
remaining results through the end of the 52nd month, that do not fall 
within a calendar quarter, must be submitted to EPA no later than 30 
days from the end of the 52nd month. The pellet quality analyses shall 
include results for the following factors: Compression, reducibility, 
before tumble, after tumble, and low temperature disintegration. For 
each of the pellet quality analysis factors, the owner or operator must 
explain the pellet quality analysis factor, as well as the defined 
acceptable range for each factor using the applicable product quality 
standards based upon customers' pellet specifications that are 
contained in United Taconite's ISO 9001 quality management system. The 
owner or operator shall provide pellet quality analysis testing results 
that state the date and time of the analysis and, in order to define 
the time period when pellets were produced outside of the defined 
acceptable range for the pellet quality factors listed, provide copies 
of the production logs that document the starting and ending times for 
such periods. The owner or operator shall provide an explanation of 
causes for pellet samples that fail to meet the acceptable range for 
any pellet quality analysis factor. Pellet quality information and data 
may be submitted to EPA as Confidential Business Information.
    (6) No later than 52 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for United Taconite Grate Kiln Line 2 within the 
upper and lower bounds described below. EPA will review the report and 
either confirm or modify the NOX limits. If the CEMS data 
collected during operating periods between months 44 and 52 that both 
meet pellet quality specifications and proper furnace/burner operation 
is normally distributed, the limit adjustment determination shall be 
based on the appropriate (depending upon whether data are statistically 
independent or dependent) 95% upper predictive limit (UPL) equations in 
paragraph (f) of this section. If the CEMS data collected during 
operating periods between months 44 and 52 that both meet pellet 
quality specifications and proper furnace/burner operation are not 
normally distributed, the limit adjustment determination shall be based 
on the non-parametric equation provided in paragraph (f) of this 
section. The data set for the determination shall exclude periods when 
pellet quality did not fall within the defined acceptable ranges of the 
pellet quality factors identified pursuant to paragraph 
(b)(1)(iv)(B)(5) of this section and for any subsequent period when 
production had been reduced in response to pellet quality concerns 
consistent with United Taconite's ISO 9001 operating standards. Any 
excluded period will commence at the time documented on the production 
log demonstrating pellet quality did not fall within the defined 
acceptable range, and shall end when pellet quality within the defined 
acceptable range has been re-established at planned production levels, 
which will be presumed to be the level that existed immediately prior 
to the reduction in production due to pellet quality concerns. EPA may 
also exclude data where operations are inconsistent with the reported 
design parameters of the NOX reduction control technology 
that were installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limits in the 
Federal Register no later than 55 months after May 12, 2016. The 
confirmed or modified NOX limit for United Taconite Grate 
Kiln Line 2 when burning only natural gas may be no lower than 2.8 lbs 
NOX/MMBTU, based on a 720-hour rolling average, and may not 
exceed 3.0 lbs NOX/MMBTU, based on a 720-hour rolling 
average. The confirmed or modified NOX limit for United 
Taconite Grate Kiln Line 2 when burning coal or a mixture of coal and 
natural gas may be no lower than 1.5 lbs NOX/MMBTU, based on 
a 720-hour rolling average, and may not exceed 2.5 lbs NOX/
MMBTU, based on a 720-hour rolling average.
    (8) If the owner or operator submits a report proposing a single 
NOX limit for all fuels, EPA may approve the proposed 
NOX limit for all fuels based on a 30-day rolling average. 
The confirmed or modified limit will be established and enforceable 
within 55 months from May 12, 2016.
    (v) ArcelorMittal USA--(A) ArcelorMittal Minorca Mine. (1) An 
emission limit of 1.2 lbs NOX/MMBTU, based on a 30-day 
rolling average, shall apply to the ArcelorMittal Minorca Mine 
indurating furnace when burning natural gas. This emission limit will 
become enforceable 55 months after

[[Page 21692]]

May 12, 2016 and only after EPA's confirmation or modification of the 
emission limit in accordance with the procedures set forth in 
paragraphs (b)(1)(v)(A)(2) through (7) of this section.
    (2) Compliance with this emission limit will be demonstrated with 
data collected by a continuous emissions monitoring system (CEMS) for 
NOX. The owner or operator of the ArcelorMittal Minorca Mine 
indurating furnace must install a CEMS for NOX and 
SO2 within six months from May 12, 2016. The owner or 
operator must start collecting CEMS data and submit the data to EPA no 
later than 30 days from the end of each calendar quarter after that 
installation deadline. Any remaining data through the end of the 52nd 
month from May 12, 2016, that does not fall within a calendar quarter, 
must be submitted to EPA no later than 30 days from the end of the 52nd 
month. Although CEMS data must continue to be collected, it does not 
need to be submitted to EPA starting 52 months after May 12, 2016.
    (3) No later than 42 months after May 12, 2016 the owner or 
operator must submit to EPA a report, including any final report(s) 
completed by the selected NOX reduction technology supplier 
and furnace retrofit engineer, containing a detailed engineering 
analysis and modeling of the NOX reduction control 
technology being installed on the ArcelorMittal Minorca Mine indurating 
furnace. The NOX reduction control technology must be 
designed to meet an emission limit of 1.2 lbs NOX/MMBTU. 
This report must include a list of all process and control technology 
variables that can reasonably be expected to have an impact on 
NOX emissions control technology performance, as well as a 
description of how these variables can be adjusted to reduce 
NOX emissions to meet the NOX design emission 
limit.
    (4) The NOX reduction control technology shall be 
installed on the ArcelorMittal Minorca Mine indurating furnace no later 
than 44 months after May 12, 2016.
    (5) Commencing on the earlier of: Six months from the installation 
of the NOX reduction control technology; or 44 months from 
May 12, 2016, the owner or operator must provide to EPA the results 
from pellet quality analyses. The owner or operator shall provide the 
results from pellet quality analyses no later than 30 days from the end 
of each calendar quarter up until 52 months after May 12, 2016. Any 
remaining results through the end of the 52nd month from May 12, 2016, 
that do not fall within a calendar quarter, must be submitted to EPA no 
later than 30 days from the end of the 52nd month. The pellet quality 
analyses shall include results for the following factors: Compression, 
reducibility, before tumble, after tumble, low temperature 
disintegration, and contraction. For each of the pellet quality 
analysis factors, the owner or operator must explain the pellet quality 
analysis factor, as well as the defined acceptable range for each 
factor using the applicable product quality standards based upon 
customers' pellet specifications that are contained in the 
ArcelorMittal Minorca Mine's Standard Product Parameters. The owner or 
operator shall provide pellet quality analysis testing results that 
state the date and time of the analysis and, in order to define the 
time period when pellets were produced outside of the defined 
acceptable range for the pellet quality factors listed, provide copies 
of production or scale data that document the starting and ending times 
for such periods. The owner or operator shall provide an explanation of 
causes for pellet samples that fail to meet the acceptable range for 
any pellet quality analysis factor. Pellet quality information and data 
may be submitted to EPA as Confidential Business Information.
    (6) No later than 52 months after May 12, 2016, the owner or 
operator may submit to EPA a report to either confirm or modify the 
NOX limits for the ArcelorMittal Minorca Mine indurating 
furnace within the upper and lower bounds described below. EPA will 
review the report and either confirm or modify the NOX 
limits. If the CEMS data collected during operating periods between 
months 44 and 52 that both meet pellet quality specifications and 
proper furnace/burner operation is normally distributed, the limit 
adjustment determination shall be based on the appropriate (depending 
upon whether data are statistically independent or dependent) 95% upper 
predictive limit (UPL) equations in paragraph (f) of this section. If 
the CEMS data collected during operating periods between months 44 and 
52 that both meet pellet quality specifications and proper furnace/
burner operation are not normally distributed, the limit adjustment 
determination shall be based on the non-parametric equation provided in 
paragraph (f) of this section. The data set for the determination shall 
exclude periods when pellet quality did not fall within the defined 
acceptable ranges of the pellet quality factors identified pursuant to 
paragraph (b)(1)(v)(A)(5) of this section and for any subsequent period 
when production has been reduced in response to pellet quality concerns 
consistent with the ArcelorMittal Minorca Mine's Standard Product 
Parameters. Any excluded period will commence at the time documented in 
related quality reports demonstrating that pellet quality did not fall 
within the defined acceptable range and shall end when pellet quality 
within the defined acceptable range has been re-established at planned 
production levels, which will be presumed to be the level that existed 
immediately prior to the reduction in production due to pellet quality 
concerns. EPA may also exclude data where operations are inconsistent 
with the reported design parameters of the NOX reduction 
control technology installed.
    (7) EPA will take final agency action by publishing its final 
confirmation or modification of the NOX limit in the Federal 
Register no later than 55 months after May 12, 2016. The confirmed or 
modified NOX limit for the ArcelorMittal Minorca Mine 
indurating furnace when burning only natural gas may be no lower than 
1.2 lbs NOX/MMBTU, based on a 30-day rolling average, and 
may not exceed 1.8 lbs NOX/MMBTU, based on a 30-day rolling 
average.
    (B) [Reserved]
* * * * *
    (2) * * *
    (iv) United Taconite: An aggregate emission limit of 529.0 lbs 
SO2/hr, based on a 30-day rolling average, shall apply to 
the Line 1 pellet furnace (EU040) and Line 2 pellet furnace (EU042) 
beginning six months after May 12, 2016. Compliance with this aggregate 
emission limit shall be demonstrated with data collected by a 
continuous emissions monitoring system (CEMS) for SO2. The 
owner or operator must start collecting CEMS data for SO2 
beginning six months after May 12, 2016 and submit the data to EPA no 
later than 30 days from the end of each calendar quarter. Beginning six 
months after May 12, 2016, any coal burned on UTAC Grate Kiln Line 1 or 
Line 2 shall have no more than 1.5 percent sulfur by weight based on a 
monthly block average. The sampling and calculation methodology for 
determining the sulfur content of coal must be described in the 
monitoring plan required for this furnace.
* * * * *
    (c) Testing and monitoring. (1) The owner or operator of the 
respective facility shall install, certify, calibrate, maintain and 
operate continuous emissions monitoring systems (CEMS) for 
NOX on United States Steel

[[Page 21693]]

Corporation, Keetac unit EU030; Hibbing Taconite Company units EU020, 
EU021, and EU022; United States Steel Corporation, Minntac units EU225, 
EU261, EU282, EU315, and EU334; United Taconite units EU040 and EU042; 
ArcelorMittal Minorca Mine unit EU026; and Northshore Mining Company-
Silver Bay units Furnace 11 (EU100/EU104) and Furnace 12 (EU110/EU114). 
Compliance with the emission limits for NOX shall be 
determined using data from the CEMS.
    (2) The owner or operator shall install, certify, calibrate, 
maintain, and operate CEMS for SO2 on United States Steel 
Corporation, Keetac unit EU030; Hibbing Taconite Company units EU020, 
EU021, and EU022; United States Steel Corporation, Minntac units EU225, 
EU261, EU282, EU315, and EU334; United Taconite units EU040 and EU042; 
ArcelorMittal Minorca Mine unit EU026; and Northshore Mining Company-
Silver Bay units Furnace 11 (EU100/EU104) and Furnace 12 (EU110/EU114).
    (3) The owner or operator shall install, certify, calibrate, 
maintain, and operate one or more continuous diluent monitor(s) 
(O2 or CO2) and continuous flow rate monitor(s) 
on the BART affected units to allow conversion of the NOX 
and SO2 concentrations to units of the standard (lbs/MMBTU 
and lbs/hr, respectively) unless a demonstration is made that a diluent 
monitor and continuous flow rate monitor are not needed for the owner 
or operator to demonstrate compliance with applicable emission limits 
in units of the standards.
    (4) For purposes of this section, all CEMS required by this section 
must meet the requirements of paragraphs (c)(4)(i) through (xiv) of 
this section.
    (i) All CEMS must be installed, certified, calibrated, maintained, 
and operated in accordance with 40 CFR part 60, appendix B, Performance 
Specification 2 (PS-2) and appendix F, Procedure 1.
    (ii) CEMS must be installed and operational as follows:
    (A) All CEMS associated with monitoring NOX (including 
the NOX monitor and necessary diluent and flow rate 
monitors) at the following facilities: U.S. Steel Keetac, U.S. Steel 
Minntac, and Northshore Mining Company-Silver Bay, must be installed 
and operational no later than the unit specific compliance dates for 
the emission limits identified at paragraphs (b)(1)(i), (iii) and (vi) 
of this section, respectively.
    (B) All CEMS associated with monitoring NOX (including 
the NOX monitor and necessary diluent and flow rate 
monitors) at the following facilities: Hibbing Taconite Company, United 
Taconite, and ArcelorMittal Minorca Mine, must be installed and 
operational no later than the unit specific installation dates for the 
installation and operation of CEMS identified at paragraphs (b)(1)(ii), 
(iv) and (v) of this section, respectively.
    (C) All CEMS associated with monitoring SO2 at the 
following facilities: U.S. Steel Keetac, U.S. Steel Minntac, and 
Northshore Mining Company-Silver Bay, must be installed and operational 
no later than six months after May 12, 2016.
    (D) All CEMS associated with monitoring SO2 at the 
following facilities: Hibbing Taconite Company, United Taconite, and 
ArcelorMittal Minorca Mine, must be installed and operational no later 
than six months after May 12, 2016.
    (E) The operational status of the CEMS identified in paragraphs 
(c)(1) and (2) of this section shall be verified by, as a minimum, 
completion of the manufacturer's written requirements or 
recommendations for installation, operation, and calibration of the 
devices.
    (iii) The owner or operator must conduct a performance evaluation 
of each CEMS in accordance with 40 CFR part 60, appendix B, PS-2. The 
performance evaluations must be completed no later than 60 days after 
the respective CEMS installation.
    (iv) The owner or operator of each CEMS must conduct periodic 
Quality Assurance, Quality Control (QA/QC) checks of each CEMS in 
accordance with 40 CFR part 60, appendix F, Procedure 1. The first CEMS 
accuracy test will be a relative accuracy test audit (RATA) and must be 
completed no later than 60 days after the respective CEMS installation.
    (v) The owner or operator of each CEMS must furnish the Regional 
Administrator two, or upon request, more copies of a written report of 
the results of each performance evaluation and QA/QC check within 60 
days of completion.
    (vi) The owner or operator of each CEMS must check, record, and 
quantify the zero and span calibration drifts at least once daily 
(every 24 hours) in accordance with 40 CFR part 60, appendix F, 
Procedure 1, Section 4.
    (vii) Except for CEMS breakdowns, repairs, calibration checks, and 
zero and span adjustments, all CEMS required by this section shall be 
in continuous operation during all periods of BART affected process 
unit operation, including periods of process unit startup, shutdown, 
and malfunction.
    (viii) All CEMS required by this section must meet the minimum data 
requirements at paragraphs (c)(4)(viii)(A) through (C) of this section.
    (A) Complete a minimum of one cycle of operation (sampling, 
analyzing, and data recording) for each successive 15-minute quadrant 
of an hour.
    (B) Sample, analyze, and record emissions data for all periods of 
process operation except as described in paragraph (c)(4)(viii)(C) of 
this section.
    (C) When emission data from CEMS are not available due to 
continuous monitoring system breakdowns, repairs, calibration checks, 
or zero and span adjustments, emission data must be obtained using 
other monitoring systems or emission estimation methods approved by the 
EPA. The other monitoring systems or emission estimation methods to be 
used must be incorporated into the monitoring plan required by this 
section and provide information such that emissions data are available 
for a minimum of 18 hours in each 24-hour period and at least 22 out of 
30 successive unit operating days.
    (ix) Owners or operators of each CEMS required by this section must 
reduce all data to 1-hour averages. Hourly averages shall be computed 
using all valid data obtained within the hour but no less than one data 
point in each 15-minute quadrant of an hour. Notwithstanding this 
requirement, an hourly average may be computed from at least two data 
points separated by a minimum of 15 minutes (where the unit operates 
for more than one quadrant in an hour) if data are unavailable as a 
result of performance of calibration, quality assurance, preventive 
maintenance activities, or backups of data from data acquisition and 
handling systems and recertification events.
    (x) The 30-day rolling average emission rate determined from data 
derived from the CEMS required by this section (in lbs/MMBTU or lbs/hr 
depending on the emission standard selected) must be calculated in 
accordance with paragraphs (c)(4)(x)(A) through (F) of this section.
    (A) Sum the total pounds of the pollutant in question emitted from 
the unit during an operating day and the previous 29 operating days.
    (B) Sum the total heat input to the unit (in MMBTU) or the total 
actual hours of operation (in hours) during an operating day and the 
previous 29 operating days.
    (C) Divide the total number of pounds of the pollutant in question 
emitted during the 30 operating days by the total heat input (or actual 
hours of operation depending on the emission limit selected) during the 
30 operating days.

[[Page 21694]]

    (D) For purposes of this calculation, an operating day is any day 
during which fuel is combusted in the BART affected unit regardless of 
whether pellets are produced. Actual hours of operation are the total 
hours a unit is firing fuel regardless of whether a complete 24-hour 
operational cycle occurs (i.e. if the furnace is firing fuel for only 
five hours during a 24-hour period, then the actual operating hours for 
that day are five. Similarly, total number of pounds of the pollutant 
in question for that day is determined only from the CEMS data for the 
five hours during which fuel is combusted.)
    (E) If the owner or operator of the CEMS required by this section 
uses an alternative method to determine 30-day rolling averages, that 
method must be described in detail in the monitoring plan required by 
this section. The alternative method will only be applicable if the 
final monitoring plan and the alternative method are approved by EPA.
    (F) A new 30-day rolling average emission rate must be calculated 
for each new operating day.
    (xi) The 720-hour rolling average emission rate determined from 
data derived from the CEMS required by this section (in lbs/MMBTU) must 
be calculated in accordance with (c)(4)(xi)(A) through (C).
    (A) Sum the total pounds of NOX emitted from the unit 
every hour and the previous (not necessarily consecutive) 719 hours for 
which that type of fuel (either natural gas or mixed coal and natural 
gas) was used.
    (B) Sum the total heat input to the unit (in MMBTU) every hour and 
the previous (not necessarily consecutive) 719 hours for which that 
type of fuel (either natural gas or mixed coal and natural gas) was 
used.
    (C) Divide the total number of pounds of NOX emitted 
during the 720 hours, as defined above, by the total heat input during 
the same 720 hour period. This calculation must be done separately for 
each fuel type (either for natural gas or mixed coal and natural gas).
    (xii) Data substitution must not be used for purposes of 
determining compliance under this section.
    (xiii) All CEMS data shall be reduced and reported in units of the 
applicable standard.
    (xiv) A Quality Control Program must be developed and implemented 
for all CEMS required by this section in accordance with 40 CFR part 
60, appendix F, Procedure 1, Section 3. The program will include, at a 
minimum, written procedures and operations for calibration checks, 
calibration drift adjustments, preventative maintenance, data 
collection, recording and reporting, accuracy audits/procedures, 
periodic performance evaluations, and a corrective action program for 
malfunctioning CEMS.
    (d) Recordkeeping requirements. (1)(i) Records required by this 
section must be kept in a form suitable and readily available for 
expeditious review.
    (ii) Records required by this section must be kept for a minimum of 
five years following the date of creation.
    (iii) Records must be kept on site for at least two years following 
the date of creation and may be kept offsite, but readily accessible, 
for the remaining three years.
    (2) The owner or operator of the BART affected units must maintain 
the records at paragraphs (d)(2)(i) through (xi) of this section.
    (i) A copy of each notification and report developed for and 
submitted to comply with this section including all documentation 
supporting any initial notification or notification of compliance 
status submitted according to the requirements of this section.
    (ii) Records of the occurrence and duration of startup, shutdown, 
and malfunction of the BART affected units, air pollution control 
equipment, and CEMS required by this section.
    (iii) Records of activities taken during each startup, shutdown, 
and malfunction of the BART affected unit, air pollution control 
equipment, and CEMS required by this section.
    (iv) Records of the occurrence and duration of all major 
maintenance conducted on the BART affected units, air pollution control 
equipment, and CEMS required by this section.
    (v) Records of each excess emission report, including all 
documentation supporting the reports, dates and times when excess 
emissions occurred, investigations into the causes of excess emissions, 
actions taken to minimize or eliminate the excess emissions, and 
preventative measures to avoid the cause of excess emissions from 
occurring again.
    (vi) Records of all CEMS data including, as a minimum, the date, 
location, and time of sampling or measurement, parameters sampled or 
measured, and results.
    (vii) All records associated with quality assurance and quality 
control activities on each CEMS as well as other records required by 40 
CFR part 60, appendix F, Procedure 1 including, but not limited to, the 
quality control program, audit results, and reports submitted as 
required by this section.
    (viii) Records of the NOX emissions during all periods 
of BART affected unit operation, including startup, shutdown, and 
malfunction in the units of the standard. The owner or operator shall 
convert the monitored data into the appropriate unit of the emission 
limitation using appropriate conversion factors and F-factors. F-
factors used for purposes of this section shall be documented in the 
monitoring plan and developed in accordance with 40 CFR part 60, 
appendix A, Method 19. The owner or operator may use an alternate 
method to calculate the NOX emissions upon written approval 
from EPA.
    (ix) Records of the SO2 emissions in lbs/MMBTUs or lbs/
hr(based on CEMS data), depending on the emission standard selected, 
during all periods of operation, including periods of startup, 
shutdown, and malfunction, in the units of the standard.
    (x) Records associated with the CEMS unit including type of CEMS, 
CEMS model number, CEMS serial number, and initial certification of 
each CEMS conducted in accordance with 40 CFR part 60, appendix B, 
Performance Specification 2 must be kept for the life of the CEMS unit.
    (xi) Records of all periods of fuel oil usage as required at 
paragraph (b)(2)(vii) of this section.
    (e) Reporting requirements. (1) All requests, reports, submittals, 
notifications, and other communications to the Regional Administrator 
required by this section shall be submitted, unless instructed 
otherwise, to the Air and Radiation Division, U.S. Environmental 
Protection Agency, Region 5 (A-18J), at 77 West Jackson Boulevard, 
Chicago, Illinois 60604.
    (2) The owner or operator of each BART affected unit identified in 
this section and CEMS required by this section must provide to the 
Regional Administrator the written notifications, reports and plans 
identified at paragraphs (e)(2)(i) through (viii) of this section. If 
acceptable to both the Regional Administrator and the owner or operator 
of each BART affected unit identified in this section and CEMS required 
by this section the owner or operator may provide electronic 
notifications, reports, and plans.
    (i) A notification of the date construction of control devices and 
installation of burners required by this section commences postmarked 
no later than 30 days after the commencement date.
    (ii) A notification of the date the installation of each CEMS 
required by this section commences postmarked no later than 30 days 
after the commencement date.
    (iii) A notification of the date the construction of control 
devices and installation of burners required by this

[[Page 21695]]

section is complete postmarked no later than 30 days after the 
completion date.
    (iv) A notification of the date the installation of each CEMS 
required by this section is complete postmarked no later than 30 days 
after the completion date.
    (v) A notification of the date control devices and burners 
installed by this section startup postmarked no later than 30 days 
after the startup date.
    (vi) A notification of the date CEMS required by this section 
startup postmarked no later than 30 days after the startup date.
    (vii) A notification of the date upon which the initial CEMS 
performance evaluations are planned. This notification must be 
submitted at least 60 days before the performance evaluation is 
scheduled to begin.
    (viii) A notification of initial compliance, signed by the 
responsible official who shall certify its accuracy, attesting to 
whether the source has complied with the requirements of this section, 
including, but not limited to, applicable emission standards, control 
device and burner installations, CEMS installation and certification. 
This notification must be submitted before the close of business on the 
60th calendar day following the completion of the compliance 
demonstration and must include, at a minimum, the information at 
paragraphs (e)(2)(viii)(A) through (F) of this section.
    (A) The methods used to determine compliance.
    (B) The results of any CEMS performance evaluations, and other 
monitoring procedures or methods that were conducted.
    (C) The methods that will be used for determining continuing 
compliance, including a description of monitoring and reporting 
requirements and test methods.
    (D) The type and quantity of air pollutants emitted by the source, 
reported in units of the standard.
    (E) A description of the air pollution control equipment and 
burners installed as required by this section, for each emission point.
    (F) A statement by the owner or operator as to whether the source 
has complied with the relevant standards and other requirements.
    (3) The owner or operator must develop and implement a written 
startup, shutdown, and malfunction plan for NOX and 
SO2. The plan must include, at a minimum, procedures for 
operating and maintaining the source during periods of startup, 
shutdown, and malfunction; and a program of corrective action for a 
malfunctioning process and air pollution control and monitoring 
equipment used to comply with the relevant standard. The plan must 
ensure that, at all times, the owner or operator operates and maintains 
each affected source, including associated air pollution control and 
monitoring equipment, in a manner which satisfies the general duty to 
minimize or eliminate emissions using good air pollution control 
practices. The plan must ensure that owners or operators are prepared 
to correct malfunctions as soon as practicable after their occurrence.
    (4) The written reports of the results of each performance 
evaluation and QA/QC check in accordance with and as required by 
paragraph (c)(4)(v) of this section.
    (5) Compliance reports. The owner or operator of each BART affected 
unit must submit semiannual compliance reports. The semiannual 
compliance reports must be submitted in accordance with paragraphs 
(e)(5)(i) through (iv) of this section, unless the Administrator has 
approved a different schedule.
    (i) The first compliance report must cover the period beginning on 
the compliance date that is specified for the affected source through 
June 30 or December 31, whichever date comes first after the compliance 
date that is specified for the affected source.
    (ii) The first compliance report must be postmarked no later than 
30 calendar days after the reporting period covered by that report 
(July 30 or January 30), whichever comes first.
    (iii) Each subsequent compliance report must cover the semiannual 
reporting period from January 1 through June 30 or the semiannual 
reporting period from July 1 through December 31.
    (iv) Each subsequent compliance report must be postmarked no later 
than 30 calendar days after the reporting period covered by that report 
(July 30 or January 30).
    (6) Compliance report contents. Each compliance report must include 
the information in paragraphs (e)(6)(i) through (vi) of this section.
    (i) Company name and address.
    (ii) Statement by a responsible official, with the official's name, 
title, and signature, certifying the truth, accuracy, and completeness 
of the content of the report.
    (iii) Date of report and beginning and ending dates of the 
reporting period.
    (iv) Identification of the process unit, control devices, and CEMS 
covered by the compliance report.
    (v) A record of each period of startup, shutdown, or malfunction 
during the reporting period and a description of the actions the owner 
or operator took to minimize or eliminate emissions arising as a result 
of the startup, shutdown or malfunction and whether those actions were 
or were not consistent with the source's startup, shutdown, and 
malfunction plan.
    (vi) A statement identifying whether there were or were not any 
deviations from the requirements of this section during the reporting 
period. If there were deviations from the requirements of this section 
during the reporting period, then the compliance report must describe 
in detail the deviations which occurred, the causes of the deviations, 
actions taken to address the deviations, and procedures put in place to 
avoid such deviations in the future. If there were no deviations from 
the requirements of this section during the reporting period, then the 
compliance report must include a statement that there were no 
deviations. For purposes of this section, deviations include, but are 
not limited to, emissions in excess of applicable emission standards 
established by this section, failure to continuously operate an air 
pollution control device in accordance with operating requirements 
designed to assure compliance with emission standards, failure to 
continuously operate CEMS required by this section, and failure to 
maintain records or submit reports required by this section.
    (7) Each owner or operator of a CEMS required by this section must 
submit quarterly excess emissions and monitoring system performance 
reports for each pollutant monitored for each BART affected unit 
monitored. All reports must be postmarked by the 30th day following the 
end of each three-month period of a calendar year (January-March, 
April-June, July-September, October-December) and must include, at a 
minimum, the requirements at paragraphs (e)(7)(i) through (xv) of this 
section.
    (i) Company name and address.
    (ii) Identification and description of the process unit being 
monitored.
    (iii) The dates covered by the reporting period.
    (iv) Total source operating hours for the reporting period.
    (v) Monitor manufacturer, monitor model number, and monitor serial 
number.
    (vi) Pollutant monitored.
    (vii) Emission limitation for the monitored pollutant.
    (viii) Date of latest CEMS certification or audit.
    (ix) A description of any changes in continuous monitoring systems, 
processes, or controls since the last reporting period.

[[Page 21696]]

    (x) A table summarizing the total duration of excess emissions, as 
defined at paragraphs (e)(7)(x)(A) through (B) of this section, for the 
reporting period broken down by the cause of those excess emissions 
(startup/shutdown, control equipment problems, process problems, other 
known causes, unknown causes), and the total percent of excess 
emissions (for all causes) for the reporting period calculated as 
described at paragraph (e)(7)(x)(C) of this section.
    (A) For purposes of this section, an excess emission is defined as 
any 30-day or 720-hour rolling average period, including periods of 
startup, shutdown, and malfunction, during which the 30-day or 720-hour 
(as appropriate) rolling average emissions of either regulated 
pollutant (SO2 and NOX), as measured by a CEMS, 
exceeds the applicable emission standards in this section.
    (B)(1) For purposes of this rule, if a facility calculates a 30-day 
rolling average emission rate in accordance with this rule which 
exceeds the applicable emission standards of this rule, then it will be 
considered 30 days of excess emissions. If the following 30-day rolling 
average emission rate is calculated and found to exceed the applicable 
emission standards of this rule as well, then it will add one more day 
to the total days of excess emissions (i.e. 31 days). Similarly, if an 
excess emission is calculated for a 30-day rolling average period and 
no additional excess emissions are calculated until 15 days after the 
first, then that new excess emission will add 15 days to the total days 
of excess emissions (i.e. 30 + 15 = 45). For purposes of this section, 
if an excess emission is calculated for any period of time within a 
reporting period, there will be no fewer than 30 days of excess 
emissions but there should be no more than 121 days of excess emissions 
for a reporting period.
    (2) For purposes of this section, if a facility calculates a 720-
hour rolling average emission rate in accordance with this rule which 
exceeds the applicable emission standards of this section, then it will 
be considered 30 days of excess emissions. If the 24th following 720-
hour rolling average emission rate is calculated and found to exceed 
the applicable emission standards of the rule as well, then it will add 
one more day to the total days of excess emissions (i.e. 31 days). 
Similarly, if an excess emission is calculated for a 720-hour rolling 
average period and no additional excess emissions are calculated until 
360 hours after the first, then that new excess emission will add 15 
days to the total days of excess emissions (i.e. 30+15 = 45). For 
purposes of this section, if an excess emission is calculated for any 
period of time with a reporting period, there will be no fewer than 30 
days of excess emissions but there should be no more than 121 days of 
excess emissions for a reporting period.
    (C) For purposes of this section, the total percent of excess 
emissions will be determined by summing all periods of excess emissions 
(in days) for the reporting period, dividing that number by the total 
BART affected unit operating days for the reporting period, and then 
multiplying by 100 to get the total percent of excess emissions for the 
reporting period. An operating day, as defined previously, is any day 
during which fuel is fired in the BART affected unit for any period of 
time. Because of the possible overlap of 30-day rolling average excess 
emissions across quarters, there are some situations where the total 
percent of excess emissions could exceed 100 percent. This extreme 
situation would only result from serious excess emissions problems 
where excess emissions occur for nearly every day during a reporting 
period.
    (xi) A table summarizing the total duration of monitor downtime, as 
defined at paragraph (e)(7)(xi)(A) of this section, for the reporting 
period broken down by the cause of the monitor downtime (monitor 
equipment malfunctions, non-monitor equipment malfunctions, quality 
assurance calibration, other known causes, unknown causes), and the 
total percent of monitor downtime (for all causes) for the reporting 
period calculated as described at paragraph (e)(7)(xi)(B) of this 
section.
    (A) For purposes of this section, monitor downtime is defined as 
any period of time (in hours) during which the required monitoring 
system was not measuring emissions from the BART affected unit. This 
includes any period of CEMS QA/QC, daily zero and span checks, and 
similar activities.
    (B) For purposes of this section, the total percent of monitor 
downtime will be determined by summing all periods of monitor downtime 
(in hours) for the reporting period, dividing that number by the total 
number of BART affected unit operating hours for the reporting period, 
and then multiplying by 100 to get the total percent of excess 
emissions for the reporting period.
    (xii) A table which identifies each period of excess emissions for 
the reporting period and includes, at a minimum, the information in 
paragraphs (e)(7)(xii)(A) through (F) of this section.
    (A) The date of each excess emission.
    (B) The beginning and end time of each excess emission.
    (C) The pollutant for which an excess emission occurred.
    (D) The magnitude of the excess emission.
    (E) The cause of the excess emission.
    (F) The corrective action taken or preventative measures adopted to 
minimize or eliminate the excess emissions and prevent such excess 
emission from occurring again.
    (xiii) A table which identifies each period of monitor downtime for 
the reporting period and includes, at a minimum, the information in 
paragraphs (e)(7)(xiii)(A) through (D) of this section.
    (A) The date of each period of monitor downtime.
    (B) The beginning and end time of each period of monitor downtime.
    (C) The cause of the period of monitor downtime.
    (D) The corrective action taken or preventative measures adopted 
for system repairs or adjustments to minimize or eliminate monitor 
downtime and prevent such downtime from occurring again.
    (xiv) If there were no periods of excess emissions during the 
reporting period, then the excess emission report must include a 
statement which says there were no periods of excess emissions during 
this reporting period.
    (xv) If there were no periods of monitor downtime, except for daily 
zero and span checks, during the reporting period, then the excess 
emission report must include a statement which says there were no 
periods of monitor downtime during this reporting period except for the 
daily zero and span checks.
    (8) The owner or operator of each CEMS required by this section 
must develop and submit for review and approval by the Regional 
Administrator a site specific monitoring plan. The purpose of this 
monitoring plan is to establish procedures and practices which will be 
implemented by the owner or operator in its effort to comply with the 
monitoring, recordkeeping, and reporting requirements of this section. 
The monitoring plan must include, at a minimum, the information at 
paragraphs (e)(8)(i) through (x) of this section.
    (i) Site specific information including the company name, address, 
and contact information.
    (ii) The objectives of the monitoring program implemented and 
information describing how those objectives will be met.
    (iii) Information on any emission factors used in conjunction with 
the

[[Page 21697]]

CEMS required by this section to calculate emission rates and a 
description of how those emission factors were determined.
    (iv) A description of methods to be used to calculate emission 
rates when CEMS data are not available due to downtime associated with 
QA/QC events.
    (v) A description of the QA/QC program to be implemented by the 
owner or operator of CEMS required by this section. This can be the QA/
QC program developed in accordance with 40 CFR part 60, appendix F, 
Procedure 1, Section 3.
    (vi) A list of spare parts for CEMS maintained on site for system 
maintenance and repairs.
    (vii) A description of the procedures to be used to calculate 30-
day rolling averages and 720-hour rolling averages and example 
calculations which show the algorithms used by the CEMS to calculate 
30-day rolling averages and 720-hour rolling averages.
    (viii) A sample of the document to be used for the quarterly excess 
emission reports required by this section.
    (ix) A description of the procedures to be implemented to 
investigate root causes of excess emissions and monitor downtime and 
the proposed corrective actions to address potential root causes of 
excess emissions and monitor downtime.
    (x) A description of the sampling and calculation methodology for 
determining the percent sulfur by weight as a monthly block average for 
coal used during that month.
    (f) Equations for establishing the upper predictive limit--(1) 
Equation for normal distribution and statistically independent data.
[GRAPHIC] [TIFF OMITTED] TR12AP16.002

Where:

x = average or mean of hourly test run data;
t[(n-1),(0.95)] = t score, the one-tailed t 
value of the Student's t distribution for a specific degree of 
freedom (n-1) and a confidence level (0.95; 0.99 for Tilden 
SO2)
s\2\ = variance of the hourly data set;
n = number of values (e.g. 5,760 if 8 months of valid lbs 
NOX/MMBTU hourly values)
m = number of values used to calculate the test average (m = 720 as 
per averaging time)

    (i) To determine if statistically independent, use the Rank von 
Neumann Test on p. 137 of data Quality Assessment: Statistical Methods 
for Practitioners EPA QA/G-9S.
    (ii) Alternative to Rank von Neumann test to determine if data are 
dependent, data are dependent if t test value is greater than t 
critical value, where:
[GRAPHIC] [TIFF OMITTED] TR12AP16.003

[rho] = correlation between data points
t critical = t[(n-2),(0.95)] = t score, the 
two-tailed t value of the Student's t distribution for a specific 
degree of freedom (n-2) and a confidence level (0.95)

    (iii) The Anderson-Darling normality test is used to establish 
whether the data are normally distributed. That is, a distribution is 
considered to be normally distributed when p > 0.05.
    (2) Non-parametric equation for data not normally distributed and 
normally distributed but not statistically independent.

m = (n + 1) * [alpha]

m = the rank of the ordered data point, when data are sorted 
smallest to largest. The data points are 720-hour averages for 
establishing NOX limits.
n = number of data points (e.g., 5040 720-hourly averages for eight 
months of valid NOX lbs/MMBTU values)
[alpha] = 0.95, to reflect the 95th percentile

    If m is a whole number, then the limit, UPL, shall be computed as:

UPL = Xm

Where:

Xm = value of the mth data point in terms of lbs SO2/hr 
or lbs NOX/MMBTU, when the data are sorted smallest to 
largest.

    If m is not a whole number, the limit shall be computed by linear 
interpolation according to the following equation.

UPL = xm = xmi[middot]md = xmi + 0.md (xmi+1 - xmi)

Where:

mi = the integer portion of m, i.e., m truncated at zero decimal 
places, and
md = the decimal portion of m

[FR Doc. 2016-07818 Filed 4-11-16; 8:45 am]
 BILLING CODE 6560-50-P
```