[Federal Register Volume 80, Number 204 (Thursday, October 22, 2015)]
[Proposed Rules]
[Pages 64160-64189]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-25023]



[[Page 64159]]

Vol. 80

Thursday,

No. 204

October 22, 2015

Part III





Environmental Protection Agency





-----------------------------------------------------------------------





40 CFR Part 52





Air Plan Approval; Minnesota and Michigan; Revision to Taconite Federal 
Implementation Plan; Proposed Rule

  Federal Register / Vol. 80 , No. 204 / Thursday, October 22, 2015 / 
Proposed Rules  

[[Page 64160]]


-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R05-OAR-2015-0196; FRL-9934-15-Region 5]


Air Plan Approval; Minnesota and Michigan; Revision to Taconite 
Federal Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

-----------------------------------------------------------------------

SUMMARY: The Environmental Protection Agency (EPA) is proposing 
revisions to a 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 proposing to revise the nitrogen oxides 
(NOX) limits for taconite furnaces at facilities owned and 
operated by Cliffs Natural Resources (Cliffs) and ArcelorMittal USA LLC 
(ArcelorMittal). We are also proposing to revise the sulfur dioxide 
(SO2) requirements at two of Cliffs' facilities. We are 
proposing these changes because new information has come to light that 
was not available when we originally promulgated the FIP on February 6, 
2013.

DATES: Comments must be received on or before November 23, 2015.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2015-0196, by one of the following methods:
    1. www.regulations.gov: Follow the on-line instructions for 
submitting comments.
    2. Email: [email protected].
    3. Fax: (312) 408-2279.
    4. Mail: Douglas Aburano, Chief, Attainment Planning and 
Maintenance Section, Air Programs Branch (AR-18J), U.S. Environmental 
Protection Agency, 77 West Jackson Boulevard, Chicago, Illinois 60604.
    5. Hand Delivery: Douglas Aburano, Chief, Attainment Planning and 
Maintenance Section, Air Programs Branch (AR-18J), U.S. Environmental 
Protection Agency, 77 West Jackson Boulevard, Chicago, Illinois 60604. 
Such deliveries are only accepted during the Regional Office normal 
hours of operation, and special arrangements should be made for 
deliveries of boxed information. The Regional Office official hours of 
business are Monday through Friday, 8:30 a.m. to 4:30 p.m., excluding 
Federal holidays.
    Instructions: Direct your comments to Docket ID Nos. EPA-R05-OAR-
2015-0196. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
www.regulations.gov, including any personal information provided, 
unless the comment includes information claimed to be Confidential 
Business Information (CBI) or other information whose disclosure is 
restricted by statute. Do not submit information that you consider to 
be CBI or otherwise protected through www.regulations.gov or email. The 
www.regulations.gov Web site is an ``anonymous access'' system, which 
means EPA will not know your identity or contact information unless you 
provide it in the body of your comment. If you send an email comment 
directly to EPA without going through www.regulations.gov your email 
address will be automatically captured and included as part of the 
comment that is placed in the public docket and made available on the 
Internet. If you submit an electronic comment, EPA recommends that you 
include your name and other contact information in the body of your 
comment and with any disk or CD-ROM you submit. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses. For additional 
instructions on submitting comments, go to Section I of the 
SUPPLEMENTARY INFORMATION section of this document.
    Docket: 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 electronically 
in www.regulations.gov or in hard copy 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, 
[email protected].

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

I. What should I consider as I prepare my comments for EPA?
II. What action is EPA taking?
III. Background
IV. Petitions for Reconsideration of 2013 Taconite FIP
V. EPA's Basis for Granting Reconsideration
VI. Basis for Proposed Revisions to 2013 Taconite FIP Requirements
VII. Statutory and Executive Order Reviews

I. What should I consider as i prepare my comments for EPA?

    When submitting comments, remember to:
    1. Identify the rulemaking by docket number and other identifying 
information (subject heading, Federal Register date, and page number).
    2. Follow directions--The EPA may ask you to respond to specific 
questions or organize comments by referencing a Code of Federal 
Regulations (CFR) part or section number.
    3. Explain why you agree or disagree; suggest alternatives and 
substitute language for your requested changes.
    4. Describe any assumptions and provide any technical information 
and/or data that you used.
    5. If you estimate potential costs or burdens, explain how you 
arrived at your estimate in sufficient detail to allow for it to be 
reproduced.
    6. Provide specific examples to illustrate your concerns, and 
suggest alternatives.
    7. Explain your views as clearly as possible, avoiding the use of 
profanity or personal threats.
    8. Make sure to submit your comments by the comment period deadline 
identified.

II. What action is EPA taking?

    On February 6, 2013, EPA promulgated a FIP that included BART 
limits for certain taconite furnaces in Minnesota and Michigan (2013 
Taconite FIP; 78 FR 8706). EPA is proposing 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.

[[Page 64161]]

Specifically, EPA is proposing to revise the NOX limits and 
compliance schedules for these four facilities and is also proposing to 
revise the SO2 requirements for Tilden Mining and United 
Taconite.

III. Background

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

    In section 169A of the 1977 Amendments to the Clean Air Act (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 Regional Haze Rule 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.
---------------------------------------------------------------------------

    \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.''
---------------------------------------------------------------------------

B. Best Available Retrofit Technology (BART)

    Section 169A of the CAA directs states, or EPA if developing a FIP, 
to 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 ``Best Available Retrofit Technology'' as determined by 
EPA. Under the Regional Haze Rule, 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.
---------------------------------------------------------------------------

    \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.''
---------------------------------------------------------------------------

    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 follows three 
steps: First, identify those sources which meet the definition of 
``BART-eligible source'' set forth in 40 CFR 51.301; \3\ second, 
determine 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 third, for each source subject to BART, 
identify the best available type and level of control for reducing 
emissions.
---------------------------------------------------------------------------

    \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.
---------------------------------------------------------------------------

    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 (PM).
    A state implementation plan (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 Regional Haze 
Rule, 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

[[Page 64162]]

Taconite FIP on July 2, 2015, based on new information raised in 
Cliffs, ArcelorMittal, 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.

IV. Petitions for Reconsideration of 2013 Taconite FIP

A. Summary of Petitions for Reconsideration

    1. National Mining Association petitioned for reconsideration 
because EPA promulgated the 2013 FIP before finalizing its disapproval 
of the Michigan and Minnesota regional haze SIPs.
    2. Michigan Department of Environmental Quality (MDEQ) petitioned 
for reconsideration because, in its view: (1) There was no information 
available prior to the close of Michigan's public comment period on 
June 23, 2010, indicating that low NOX burners (LNBs) had 
been successfully utilized on indurating furnaces; (2) the FIP schedule 
for compliance did not provide sufficient time for the permitting 
process necessary for the installation of the LNBs; and (3) EPA had not 
followed proper procedure by finalizing the FIP for Tilden while at the 
same time asking for additional comment on the SIP disapproval for 
Tilden.
    3. Congressman Richard M. Nolan petitioned for reconsideration 
because, in his view: (1) New information came to his attention 
concerning the accuracy of EPA's visibility modeling; (2) the 
feasibility of LNB technology was not established at the time EPA 
intervened in the process; and (3) it was doubtful that LNBs could be 
successfully installed and operated in the 26 months called for in the 
FIP.
    4. Minnesota Pollution Control Agency (MPCA) petitioned for 
reconsideration of the compliance schedules in the FIP and asked for a 
10-month extension of the compliance deadlines for affected facilities 
with more than one affected process line to provide adequate time for 
MPCA to issue the required air quality permits.
    5. Cliffs petitioned for reconsideration because of perceived 
procedural defects in EPA's decision to issue the FIP rule while it was 
simultaneously evaluating Minnesota and Michigan's SIPs. Cliffs also 
raised technical issues based on new information not available at the 
time EPA promulgated the 2013 FIP. These technical issues included the 
following: (a) The FIP imposed a new 0.60% sulfur limit on coal 
combusted at United Taconite that was not proposed and was 
inappropriate because it would require the use of a new type of coal 
that the facility is not designed to handle, (b) the 2013 FIP restricts 
Tilden to combusting natural gas instead of coal, and (c) installation 
of LNBs will require a minimum of 34 months for the first straight-
grate furnace and a minimum of 39 months for the first grate kiln 
furnace, instead of the 26 months provided in the original 2013 FIP 
compliance schedule. Cliffs also provided additional evidence that, in 
its view, indicates that installation and operation of LNBs would be 
more costly and would require more time to install than EPA estimated, 
including (1) estimates by furnace engineers and burner manufacturers 
that LNB capital costs for Cliffs' furnaces will be a minimum of 4-5 
times higher than EPA's Minntac-based cost estimate,(2) estimates by 
Cliffs' furnace designer, Metso Minerals (Metso), and burner 
manufacturer, Fives North America (Fives), that there would be an 
energy penalty of 20-40% while operating the LNBs, and (3) an analysis 
by Metso indicating that Cliffs would lose approximately $195 million 
in production costs across its six lines because installing LNB cannot 
be accomplished within normal annual outage time and will also impair 
production during the shakedown period after installation.
    6. ArcelorMittal petitioned for reconsideration because of 
perceived procedural defects in EPA's decision to finalize the 2013 
Taconite FIP while still working to evaluate Minnesota's SIP. 
ArcelorMittal claimed that EPA can only issue a FIP after it has fully 
and properly evaluated the SIP, found it to be deficient, and provided 
a reasonable opportunity for the state to address EPA's concerns. 
ArcelorMittal also raised the following technical issues in the 
attachment to its petition for reconsideration: (1) The costs of LNBs, 
(2) the lack of any existing straight-grate furnaces with LNB 
technology and the resulting unwillingness of vendors to provide 
performance guarantees, (3) significant production losses because of 
the downtime resulting from installation and adjustment of LNBs at 
Hibbing, and (4) energy penalties due to the need for 25% more natural 
gas at Hibbing and 10% to 20% more natural gas at Minorca to operate 
the LNBs.
    7. U.S. Steel petitioned for reconsideration because it had 
obtained new information showing that variations in kiln configuration 
may have a substantial impact on the cost and performance of LNBs 
installed on grate-kiln furnaces. In its November 26, 2013 petition for 
reconsideration of the September 30, 2013 partial disapproval of the 
Michigan and Minnesota regional haze SIPs, Cliffs referenced U.S. 
Steel's petition for reconsideration in which it cited concerns related 
to the high costs and energy penalties associated with the installation 
of LNBs, as well as pellet quality issues.

B. Issues for Which EPA Has Granted Reconsideration

    EPA believes that the new information contained in the petitions 
for reconsideration, as well as other supporting information provided 
by Cliffs, represents significant new information that warrants 
reconsideration of many of the emission limits that EPA promulgated for 
the taconite facilities in 2013. As a result, on July 2, 2015, EPA sent 
letters to Cliffs, ArcelorMittal, and Michigan granting portions of 
their petitions for reconsideration. Specifically, EPA is granting 
reconsideration, pursuant to section 307(d)(7)(b) of the CAA, of the 
NOX and SO2 emission limits for the grate-kiln 
furnaces and the NOX emission limits for the straight-grate 
furnaces listed in the following table.

----------------------------------------------------------------------------------------------------------------
               State                     Facility--owner             Unit(s)                 Pollutant(s)
----------------------------------------------------------------------------------------------------------------
Minnesota..........................  United Taconite--       Grate-Kiln Lines 1 and  NOX and SO2.
                                      Cliffs.                 2.
Minnesota..........................  Minora Mine--           Straight-Grate Line 1.  NOX.
                                      ArcelorMittal.
Minnesota..........................  Hibbing Taconite--      Straight-Grate Lines 1- NOX.
                                      Cliffs (operator and    3.
                                      part owner).
                                     ArcelorMittal (part
                                      owner).
                                     U.S. Steel (part
                                      owner).
Michigan...........................  Tilden Mining--Cliffs.  Grate-Kiln Line 1.....  NOX and SO2.
----------------------------------------------------------------------------------------------------------------


[[Page 64163]]

    The U.S. taconite iron ore industry uses two types of pelletizing 
machines or processes: Straight-grate kilns and grate-kilns. In a 
straight-grate kiln, a continuous bed of agglomerated green pellets is 
carried through different temperature zones with upward draft or 
downward draft blown through the pellets on the metal grate. The grate-
kiln system consists of a traveling grate, a rotary kiln, and an 
annular cooler. A significant difference between these designs is that 
straight-grate kilns do not burn coal and therefore have a much lower 
potential for emitting SO2. Further, even within the same 
kiln type or process, individual (referred to as indurating or 
pelletizing) furnaces or processes have distinct equipment and process 
characteristics that may affect the compatibility and performance of 
certain types of burners. The differences between these kilns and 
processes form a key basis for the changes to the emissions limits 
proposed in this action.
    EPA is not reconsidering all elements of its 2013 FIP. The 2013 FIP 
contains SO2 and NOX limits for U.S. Steel's 
Minntac and Keetac taconite furnaces in Minnesota. EPA has not granted 
U.S. Steel's petition and is not proposing any revisions of the BART 
limits for these U.S. Steel facilities at this time. Also, EPA is not 
reconsidering the NOX limits at Cliffs' Northshore taconite 
plant because this facility is already complying with the 1.2 pounds 
per million Btu (lb/mmBtu) NOX limit in the 2013 FIP. 
Finally, EPA is not reconsidering the SO2 limits at the 
Hibbing, ArcelorMittal, or Northshore straight-grate furnaces.

V. EPA's Basis for Granting Reconsideration

    The 2013 Taconite FIP established BART NOX limits for 
all straight-grate and grate-kiln taconite furnaces. The limits are 1.2 
lbs NOX/MMBtu when burning natural gas and 1.5 lbs/MMBtu 
when burning a gas/coal mix. These limits were based upon the 
performance of high stoichiometric (high-stoich) LNBs \4\ at two of 
U.S. Steel Minntac's grate-kilns. As explained in more detail below, we 
granted reconsideration of the NOX limits for the United 
Taconite and Tilden grate-kilns, as well as for the Hibbing and 
ArcelorMittal straight-grate kilns, because information that became 
available after the close of the public comment period (September 28, 
2012) suggests that the installation of high-stoich LNBs at these 
furnaces could lead to serious technical hurdles. In addition, we 
granted reconsideration of the SO2 limits for the United 
Taconite and Tilden grate-kilns because of information that became 
available after the close of the public comment period regarding the 
inability of United Taconite to handle and burn very low sulfur coal 
and Tilden's intent to burn mixed fuels.
---------------------------------------------------------------------------

    \4\ Stoichiometry refers to the relationship between the actual 
quantity of combustion air to the theoretical minimum quantity of 
air needed for 100 percent combustion of the fuel.
---------------------------------------------------------------------------

    In determining whether to grant reconsideration of certain 
provisions of the 2013 Taconite FIP, the requirements of section 
307(d)(7)(B) of the CAA apply. Section 307(d)(7)(B) provides a two-step 
test to determine whether reconsideration should be granted. The 
petitioner must first show that it was impracticable to raise the 
comment or objection within the time period for public comment of the 
rule, or, that the grounds for the comment or objection arose after the 
period for public comment. Secondly, the petitioner must show that the 
comment or objection is of ``central relevance to the outcome of the 
rule.''
    Cliffs and ArcelorMittal provided significant new information in 
their petitions for reconsideration and supplemental submittals 
directly relevant to the outcome of the 2013 Taconite FIP. The 
following discussion details the new information upon which EPA is 
relying to base reconsideration of the BART emission limits and 
compliance schedules for these facilities, and how the information 
meets the criteria of section 307(d)(7)(B) of the CAA.

A. United Taconite

1. NOX Emission Limit
    EPA determined the NOX emission limits for BART in the 
2013 Taconite FIP primarily from data arising from the installation of 
high-stoich LNBs at U.S. Steel Minntac's furnaces 6 and 7. Although the 
United Taconite furnaces and the Minntac furnaces are all grate-kiln 
furnaces, Cliffs provided new information after the close of the 
comment period that described various differences between the furnaces. 
These differences included the structure of the kiln, the use of pre-
heaters, and the types of ore and pellets processed. Cliffs indicated 
that because of these differences, the installation of high-stoich LNBs 
at United Taconite would likely result in the impairment of pellet 
quality and production, as well as increased fuel usage and emissions. 
Cliffs subsequently provided modeling analyses that detailed the 
impacts arising from the installation of high-stoich LNBs at United 
Taconite.
    Cliffs submitted a declaration by Eric Wagner (of Metso) dated 
November 26, 2013, which describes the differences relevant to 
NOX emissions between US Steel's Minntac furnaces 6 and 7, 
upon which the 2013 Taconite FIP NOX limits were based, and 
Cliffs' grate-kiln furnaces at United Taconite. The declaration 
describes several differences that EPA believes are relevant to the 
development of BART NOX emission limits. For example, 
whereas United Taconite uses a single large kiln burner, Minntac 
furnaces 6 and 7 operate preheat burners, which supply about one-third 
of the heat input from fuel, in addition to a large kiln burner. The 
smaller preheat burners at Minntac achieve very low NOX 
rates (0.1-0.3 lbs/MMBtu) due to a more favorable NOX 
reduction combustion environment in the preheat zone as compared to the 
firing end of the kiln. Correspondingly, the lower NOX 
emissions from the preheaters result in a lower combined NOX 
emission rate than the emissions arising from a large single kiln LNB.
    Another example in the declaration notes that the ore processed at 
the facilities is different, resulting in different heat values. U.S. 
Steel's Minntac facility processes an ore high in magnetite that 
contributes heat to the kiln when oxidized. Correspondingly, by 
processing high magnetite ore at Minntac furnaces 6 and 7, U.S. Steel 
is able to effectively use ported kilns to maximize the benefit of the 
ore. Ported kilns allow the introduction of additional air directly to 
the kilns which helps oxidize the high magnetite ore, and changes the 
heat balance of the furnace. In contrast, United Taconite processes 
ores with a lower concentration of magnetite than the ore processed at 
Minntac, and correspondingly, cannot effectively use ported kilns. 
Because ported kilns change the heat balance of the furnace, U.S 
Steel's experience with high-stoich LNBs at the Minntac furnaces may 
not be directly applicable to the United Taconite furnaces.
    A final example from the declaration states that the application of 
high-stoich LNB technology at United Taconite would require additional 
air to reduce burner flame temperature, which would result in increased 
airflow through the grate drying section and increased pressure drop 
across the greenballs, which are the raw feed to the indurating 
furnace. This higher bed pressure would result in deformed pellets, 
reduced pellet quality, and lost production. Further, the increased air 
flow would also likely cause pellet breakage that would reduce 
production. The declaration notes that to avoid these

[[Page 64164]]

impacts, United Taconite likely would have to limit the dryer section 
air flow and drying rate by reducing the amount of recovered heat from 
the cooler. However, any unrecovered heat would have to be replaced 
with additional heat from the burner, with corresponding increased fuel 
usage and emissions.
    Subsequent to the submission of the declaration, Cliffs provided a 
modeling analysis that supported the information provided in the 
declaration. A report by Metso dated August 7, 2014, entitled 
``Technical Analysis for applying LNB technology to (United Taconite) 
UTAC Line 2 Grate-Kiln,'' provides a detailed analysis of expected 
impacts from using high-stoich LNBs on pellet quality, fuel usage, and 
emissions. Metso analyzed the effects of LNB technology on the United 
Taconite Line 2 Grate-Kiln by using simulation modeling in which Metso 
compared Line 2's normal operating conditions, which result in the 
production of quality pellets, with simulations performed using high-
stoich LNBs (which are the basis of the 2013 Taconite FIP limits). The 
report indicates that to maintain airflow, temperature, and pressures 
sufficient to minimize pellet quality issues would require a 
significant increase in fuel rates and corresponding emissions. 
Further, the use of high-stoich LNBs would result in decreased oxygen 
in the preheat zone gases from the kiln. The corresponding reduction in 
the oxidation heat on the grate would result in lower pellet 
temperatures at the point where the pellets leave the grate and enter 
the kiln. This would likely result in pellet breakage and a 
corresponding reduction in production.
    Finally, Cliffs provided additional information to EPA in a July 
28, 2014 meeting, which Cliffs summarized in an August 8, 2014 letter 
to EPA. The information provided included data comparing performance, 
costs, and fuel usage between high-stoich LNBs and low-stoich LNBs. 
Much of the information set forth in the August 8 letter is presented 
in section VI of this notice, pertaining to the NOX BART 
analysis. In general, the information pertains to advantages of the 
low-stoich LNBs over the high-stoich LNBs.
    The information provided by Cliffs in its petition for 
reconsideration and subsequent submittals arose from recent, time-
consuming research and analysis that could not have been completed and 
made available during the public comment period. Therefore, Cliffs has 
met the first requirement of the criteria for reconsideration set forth 
at section 307(d)(7)(B) of the CAA. Significantly, the information that 
Cliffs provided is of central relevance to the outcome of the 2013 
Taconite FIP. EPA extensively based its NOX BART analysis on 
the results arising from the installation of high-stoich LNBs at U.S. 
Steel's Minntac furnaces 6 and 7. Step one of a BART analysis requires 
the identification of all available retrofit control technologies. Step 
two of a BART analysis requires the elimination of technically 
infeasible control technologies. The new information provided by Cliffs 
directly bears on the evaluation of the selection and feasibility of 
high-stoich LNBs for use in the grate-kiln indurating furnaces at the 
United Taconite facility. On this basis, we granted reconsideration of 
the NOX determination for United Taconite (Lines 1 and 2) 
and for the corresponding emission limits and compliance schedule.
2. SO2 Emission Limit
    The 2013 Taconite FIP set a 0.60% sulfur limit on coal combusted at 
United Taconite. We promulgated this limit in response to a proposal by 
Cliffs to use low sulfur fuel at United Taconite to decrease baseline 
SO2 emissions. However, Cliffs did not have an opportunity 
to comment on the specific numeric stringency of the limit we 
promulgated. In other words, it was impracticable for Cliffs to comment 
on the final sulfur limit prior to the close of the public comment 
period.
    In its petition for reconsideration, Cliffs also presented new 
information directly pertaining to the criteria for determining BART 
limits. Cliffs stated that the United Taconite facility had been 
designed to handle and burn eastern bituminous coal, not the low 
sulfur, western subbituminous coals from the Powder River Basin (PRB) 
that Cliffs would be required to use to meet the 0.60% sulfur content 
limit. For example, PRB coal is more prone to explosion and fire and 
has a lower heat value than eastern bituminous coal. These differences, 
among others, would require Cliffs to expend significant costs to 
change operations, address safety issues, and increase the amount of 
coal required to be burned to meet furnace and pellet temperature 
requirements.
    The information that Cliffs presented pertains to the feasibility 
and costs of implementing the sulfur limit, which are criteria to be 
used in determining BART. Therefore, the information provided by Cliffs 
after the close of the comment period is of central relevance to the 
outcome of the 2013 Taconite FIP. On this basis, we granted 
reconsideration of the 0.60% sulfur limit on coal combusted at United 
Taconite.

B. Tilden

1. NOX Emission Limit
    EPA determined the NOX emission limits for BART in the 
2013 Taconite FIP primarily from data arising from the installation of 
high-stoich LNBs at U.S. Steel's Minntac furnaces 6 and 7. Although the 
Tilden furnace and the Minntac furnaces are all grate-kiln furnaces, 
Cliffs provided new information after the close of the comment period 
that described various differences between the furnaces. These 
differences included the structure of the kiln, the use of pre-heaters, 
and the ore and pellet types processed. Cliffs indicated that because 
of these differences, the installation of high-stoich LNBs at Tilden 
would likely result in the impairment of pellet quality and production, 
as well as increased fuel usage and emissions. Cliffs subsequently 
provided a modeling analysis that detailed the impacts arising from the 
installation of high-stoich LNBs at Tilden.
    Cliffs submitted a declaration by Eric Wagner (of Metso) dated 
November 26, 2013, which describes the differences relevant to 
NOX emissions between U.S. Steel's Minntac furnaces 6 and 7, 
upon which the 2013 Taconite FIP NOX limits were based, and 
Cliffs' grate-kiln furnaces at Tilden. The declaration describes 
several differences that EPA believes are relevant to the development 
of BART NOX emission limits. For example, whereas Tilden 
uses a single large kiln burner, Minntac furnaces 6 and 7 operate 
preheat burners, which supply about one third of the heat input from 
fuel, in addition to a large kiln burner. The smaller preheat burners 
at Minntac achieve very low NOX rates (0.1-0.3 lbs/MMBtu) 
due to a more favorable NOX reduction combustion environment 
in the preheat zone as compared to the firing end of the kiln. 
Correspondingly, the lower NOX emissions from the preheaters 
result in a lower combined NOX emission rate than the 
emissions arising from a large single kiln LNB.
    Another example in the declaration notes that the ore processed at 
the facilities is different, resulting in different heat values. U.S. 
Steel's Minntac facility processes an ore high in magnetite that 
contributes heat to the kiln when oxidized. Correspondingly, by 
processing high magnetite ore at Minntac furnaces 6 and 7, U.S. Steel 
is able to effectively use ported kilns to maximize the benefit of the 
ore. Ported kilns allow the introduction of additional air directly to 
the kilns, which helps oxidize the high magnetite ore and changes the 
heat balance of the

[[Page 64165]]

furnace. In contrast, Tilden primarily processes hematite, which is not 
a source of heat for kilns. Correspondingly, Tilden cannot effectively 
use ported kilns. Because ported kilns change the heat balance of the 
furnace, U.S. Steel's experience with high-stoich LNBs at the Minntac 
furnaces may not be directly applicable to the Tilden furnace.
    A final example from the declaration states that the application of 
high-stoich LNB technology at Tilden would require additional air to 
reduce burner flame temperature, which would result in increased 
airflow through the grate drying section and increased pressure drop 
across the greenballs. This higher bed pressure would result in 
deformed pellets and reduced pellet quality. Further, the increased air 
flow would also likely cause pellet breakage which would reduce 
production. The declaration notes that to likely avoid these impacts, 
Tilden would have to limit the dryer section air flow and drying rate 
by reducing the amount of recovered heat from the cooler. However, any 
unrecovered heat would have to be replaced with additional heat from 
the burner, with corresponding increased fuel usage and emissions.
    In addition to the submission of the November 26, 2013 declaration, 
Cliffs provided modeling and technical analyses that supported the 
comments made in the declaration. In reports prepared by Metso dated 
September 14, 2012, and January 13, 2015, Cliffs provided technical 
analyses for applying LNB technology to the Tilden Line 1 grate kiln 
through modeling simulations that compare current operations to 
operations using high-stoich LNBs. Current operating conditions at 
Tilden 1 were simulated using such factors as existing air flow 
studies, operating parameters, and feed mineralogy. This baseline model 
was then modified to simulate LNB operating conditions. The current 
operating parameters and anticipated high-stoich LNB operating 
conditions were then compared.
    High-stoich LNBs reduce NOX emissions by introducing 
comparatively large amounts of cooler ambient air through the main 
burner. Less NOX is produced at lower temperatures. The FIP 
NOX limits were established based upon high-stoich LNBs 
operating with air flow at 100 percent of stoichiometric through the 
primary burner. Tilden currently operates with primary combustion air 
at 15.5 percent of stoichiometric, and Metso estimated that primary 
combustion air at 100 to 110 percent of the stoichiometric rate is 
required to meet the 2013 Taconite FIP limits. Metso performed three 
simulations in which it maintained peak pellet temperature and final 
product temperature. The total air supplied to the cooler was adjusted 
as needed to maintain final product temperature across all three 
simulations. These simulations were intended to isolate the effects of 
various process parameters when applying high-stoich LNB technology to 
Tilden 1.
    The analysis indicated, among other things, that high-stoich LNB 
technology would alter the flame temperature profile, which may 
adversely affect pellet quality, and that the fuel usage rate would 
increase by approximately 25 to 35 percent. Further, higher 
temperatures and air flow rates through the grate would result in a 10 
to 20 percent increase in exhaust gas volumes.
    The Metso comparative analysis dated January 2015 applies current 
operating data to the high-stoich LNB design conditions, required for 
NOX reduction, provided by COEN Company (COEN), a burner 
manufacturer, in its Final Report for Tilden Line 1. The engineering 
simulations held key process parameters constant, including pellet 
production rate, greenball moisture, bentonite, and flux rate. The 
total air supplied to the cooler was adjusted as needed to maintain 
final product temperature across all simulations. Maintaining these 
parameters ensures that fuel changes are not due to altered processing 
requirements.
    The engineering simulations and comparisons reveal a number of 
significant operational and environmental impacts arising from the 
installation of a COEN high-stoich LNB. These impacts include a 
significant change to the use of primary and secondary cooling air, 
which will alter the cooling down cycle of pellets, create an imbalance 
between primary and secondary cooling, and likely affect pellet 
quality. The volume of secondary cooling air exiting the cooler vent 
stack is projected to increase between 415 and 360 percent. This may 
adversely affect the process and pellet quality and also increase dust 
loading. Further, the increase in unheated primary combustion air to 
the burner will require an increase in fuel to replace the heat not 
used from heated secondary combustion air. It is expected that this 
will result in an increase in the fuel rate from between 21 to 28 
percent. In addition, the high-stoich LNB will alter the flame 
temperature profile, which may affect pellet quality.
    The information provided by Cliffs in its petition for 
reconsideration and subsequent submittals arose from recent, time-
consuming research and analysis that could not have been completed and 
made available during the public comment period. Therefore, Cliffs has 
met the first requirement of the criteria for reconsideration set forth 
in section 307(d)(7)(B) of the CAA. Significantly, the information that 
Cliffs provided is of central relevance to the outcome of the 2013 
Taconite FIP. EPA extensively based its NOX BART analysis on 
the results arising from the installation of high-stoich LNBs at U.S. 
Steel's Minntac furnaces 6 and 7. Step one of a BART analysis requires 
the identification of all available retrofit control technologies. Step 
two of a BART analysis requires the elimination of technically 
infeasible control technologies. The new information provided by Cliffs 
directly bears on the selection and feasibility of high-stoich LNBs for 
use in the grate-kiln indurating furnace at the Tilden facility. On 
this basis, we granted reconsideration of the NOX 
determination for Tilden (grate-kiln line 1) and for the corresponding 
emission limits and compliance schedule.
2. SO2 Emission Limit
    The 2013 Taconite FIP required the Tilden grate-kiln Line 1 to burn 
100% natural gas. However, although mentioned in discussions with 
Cliffs, this requirement had not been proposed before the final rule. 
Therefore, it was impracticable for Cliffs to comment on the final BART 
requirement to burn solely natural gas.
    Cliffs more recent intent to burn mixed fuels at Tilden is new 
information that we did not consider in determining BART for Tilden. 
The burning of mixed fuels will significantly increase SO2 
emissions, resulting in Cliffs' inability to meet the BART limit. 
Therefore, the new information is of central relevance to the outcome 
of the 2013 Taconite FIP. On this basis, we granted reconsideration to 
the 2013 Taconite FIP requirement to burn only natural gas at the 
Tilden grate-kiln Line 1.

C. ArcelorMittal Minorca Mine and Hibbing Taconite: NOX 
Limit

    The 2013 Taconite FIP established NOX emission limits 
for both grate-kiln and straight-grate kiln taconite furnaces. The 
limits that EPA developed were based solely upon the performance of 
high-stoich LNBs installed at two of U.S. Steel Minntac's grate-kilns. 
However, as explained above, there are significant differences between 
straight-grate kiln and grate-kiln furnaces that must be considered in 
setting emissions limits.

[[Page 64166]]

    ArcelorMittal's Minorca taconite facility and the Hibbing taconite 
facility, which is jointly owned by Cliffs, ArcelorMittal, and U.S. 
Steel, operate straight-grate furnaces that are required to meet the 
1.2 lbs NOX/MMBT BART limit under the 2013 Taconite FIP. In 
the petitions for reconsideration submitted by ArcelorMittal and 
Cliffs, the petitioners provided new information directly bearing on 
the criteria used to establish BART NOX limits. Their 
comments reflected similar issues to those that Cliffs presented in its 
analysis of grate-kiln furnaces at the United Taconite and Tilden 
facilities, including cost, increased fuel usage, the potential impact 
on production, and the feasibility of meeting the BART NOX 
limit. Further, it is significant that at the time of promulgation of 
the 2013 Taconite FIP, no LNB had been installed on a straight grate 
furnace. Correspondingly, ArcelorMittal reported that none of the 
vendors it had contacted were willing to guarantee the successful 
installation or operation of a LNB on a straight-grate furnace.
    The information provided by ArcelorMittal and Cliffs in their 
petitions for reconsideration and subsequent submittals arose from 
recent, time-consuming research and analysis that was not and could not 
have been completed and made available during the public comment 
period. Therefore, they have met the first requirement of the criteria 
for reconsideration set forth at section 307(d)(7)(B) of the CAA. The 
new information provided by the petitioners directly addresses the 
costs and feasibility of LNB controls, which are criteria to be used in 
determining BART. The cost and feasibility of the LNB controls are of 
central relevance to the outcome of the 2013 Taconite FIP. On this 
basis, we granted reconsideration to the NOX BART limits for 
straight grate taconite furnaces at the ArcelorMittal Minorca facility 
and the Hibbing facility.

VI. Basis for Proposed Revisions to 2013 Taconite FIP Requirements

A. Revised BART Determinations

i. United Taconite and Tilden Grate-Kilns--Five Step BART Evaluation 
for NOX
(1) Step 1: Identify All Available Retrofit Control Technologies
    As discussed in the August 15, 2012 proposed FIP, the following 
control technologies were identified: external flue gas recirculation, 
low-NOX burners, induced flue gas recirculation burners, 
energy efficiency projects, ported kilns, and selective catalytic 
reduction (SCR). High-stoich and low-stoich low-NOX burners 
were subsequently considered separately.
(2) Step 2: Eliminate Technically Infeasible Options
    External flue gas recirculation and induced flue gas recirculation 
burners were eliminated from consideration since they are technically 
infeasible for the specific application to pellet furnaces due to the 
high oxygen content of the flue gas. Energy efficiency projects were 
eliminated due to the difficulty of assigning a general potential 
emission reduction for this category. EPA agrees that SCR controls are 
infeasible for indurating furnaces based on two SCR vendors declining 
to bid on NOX reduction testing at Minntac. The following 
three Metso reports provide detailed analyses of expected adverse 
impacts of using high-stoich LNBs, which are in use at U.S. Steel 
Minntac, on both pellet quality and increased fuel use: an August 7, 
2014, report entitled ``Technical Analysis for applying LNB technology 
to United Taconite Line 2 Grate-Kiln,'' a September 14, 2012 report 
titled ``Technical Analysis for Appling LNB Technology to Tilden 1 
Grate Kiln System,'' and a January 13, 2015 report titled ``Technical 
Analysis for Tilden Phase III Additional Simulations while Applying 
COEN LNB Technology.'' A summary of the results from these Metso 
reports is contained in an August 13, 2015 technical support document.
    A mass emission rate comparison between high-stoich and low-stoich 
LNB options was presented by Metso, during a July 28, 2014 meeting 
between EPA and Cliffs and summarized in a subsequent August 8, 2014 
letter to EPA. Metso's analysis compared the amount of NOX 
that would be generated when a furnace is retrofitted with a high-
stoich LNB and low-stoich staged combustion LNB options. This analysis 
demonstrated that although the lbs NOX/MMBtu may be lower 
from a high-stoich burner, the high-stoich LNB will require more fuel 
(and BTUs) and result in higher NOX emissions. A more 
detailed discussion of this analysis is contained in an August 13, 2015 
technical support document.
    The declaration by Eric Wagner (of Metso) dated November 26, 2013 
consists mainly of a description of differences relevant to 
NOX emissions between U.S. Steel's Minntac furnaces 6 and 7, 
upon which the 2013 Taconite FIP NOX limits were based, and 
Cliffs' grate-kiln furnaces at Tilden and United Taconite. The 
declaration noted these differences:

--Minntac furnaces 6 and 7 operate preheat burners, which supply about 
one third of the heat input from fuel, in addition to the large kiln 
burner. United Taconite and Tilden use a single kiln burner. These 
smaller preheat burners can achieve very low NOX rates (0.1-
0.3 lbs/MMBtu) due to a more favorable NOX reduction 
combustion environment in the preheat zone as compared to the firing 
end of the kiln. These lower NOX emissions produce a lower 
combined NOX rate than from the large kiln LNB.
--Minntac furnaces 6 and 7 process high magnetite ore that contributes 
heat to the kiln when oxidized. Tilden's ores are primarily hematite, 
which is not a source of heat for the kilns, and United Taconite 
processes ores with a lower concentration of magnetite than Minntac. 
Therefore, Tilden and United Taconite's furnaces must add more fuel to 
achieve final product requirements than Minntac. The associated energy 
penalties are predicted to remain 25-45 percent for Cliffs' grate-kiln 
furnaces even after energy efficiency improvements at United Taconite 
and Tilden.
--Minntac furnaces 6 and 7 use ported kilns to maximize the benefit of 
their high magnetite ore bodies. Ported kilns allow the introduction of 
additional air directly to the kilns where it helps to oxidize the high 
magnetite ore that Minntac processes. United Taconite and Tilden do not 
use ported kilns because porting will not produce significant benefits 
for the type of ore they process. Ported kilns significantly change the 
heat balance of the furnace, making it difficult to generalize from 
Minntac's experience.
--Minntac furnaces 6 and 7 are also unique because they produce high 
flux magnetite pellets. By contrast, United Taconite produces primarily 
standard (low flux) magnetite pellets, and Tilden produces high flux 
hematite pellets. Retrofitting a furnace with the Coen-type high-stoich 
LNB burner introduces more air, requires more fuel, and at different 
locations. As a result, the high-stoich LNB retrofit must be evaluated 
in the context of the unique furnace design for that specific pellet 
product from that specific ore type. The Minntac experience cannot 
therefore be generalized to other furnaces.
--The application of high-stoich LNB technology at Tilden and United 
Taconite would require additional air to reduce burner flame 
temperature, which would result in increased airflow through the grate 
drying

[[Page 64167]]

section and increased pressure drop across the greenballs. This higher 
bed pressure would result in deformed pellets and reduced pellet 
quality. The increased air flow would also cause pellet breakage 
leading to decreased production. In order to maintain pellet quality 
and production rate, the overall dryer section air flow and drying rate 
must be limited by reducing the amount of recovered heat from the 
cooler. This unrecovered heat must be replaced with additional burner 
fuel, further increasing fuel requirements.

    EPA agrees with the results of the Metso reports and declaration 
and have therefore determined that high-stoich LNBs are technically 
infeasible for the United Taconite and Tilden grate-kilns. Low-stoich 
grate-kilns remain technically feasible for grate-kilns.
(3) Step 3: Evaluate Control Effectiveness of Remaining Control 
Technologies
    Low-stoich burners, as designed by FCT Combustion (FCT), are 
expected to avoid the previously described drawbacks from high-stoich 
burners and can be designed to meet 2.8 lbs/MMBtu when burning natural 
gas and 1.5 lbs/MMBtu when burning a gas/coal mix. This technology is 
described in the ``FCT Combustion Cliffs UTAC Line 2 Phase 3 Modeling 
Report'' and August 8, 2014 letter from Douglas McWilliams. FCT 
supplies a LNB, called the FCT COMBUSTION Gyro-Therm MKII burner. This 
FCT low-stoich Gyro-Therm burner design achieves NOX 
reductions by reducing flame temperature by mixing fuel and air to 
simulate the effects of staged combustion for NOX reduction. 
This burner uses a special gas nozzle that injects the gas in a 
stirring type of motion. The fluid mechanics resulting from use of this 
nozzle create a dramatically different flame and NOX is 
greatly reduced through natural staging of the fuel-air mixing. This 
FCT low-stoich LNB would not require additional primary air, which 
would eliminate the air velocity and pressure contributions to pellet 
quality problems. FCT's proposed low-stoich burner also does not 
require substantial additional fuel because it is not introducing cool 
primary air that must be heated to sustain critical furnace 
temperatures.
    FCT performed CFD modeling at United Taconite in order to design a 
new burner that will reduce NOX, but maintain product 
quality, production and optimize fuel efficiency. The modeling for 
combusting solely natural gas indicated a reduction from a base case of 
5.3-6.4 lb NOX/MMBtu to 2.91 lbs NOX/MMBtu; the 
modeling for co-firing at 30 percent gas and 70 percent coal indicated 
a reduction from a base case of 1.6-5.4 (although the upper bound is 
generally closer to 2.8 lbs/MMBtu), with a typical baseline value of 
2.5 lbs/MMBtu, to 2.04 lbs NOX/MMBtu. The NOX 
reduction technology appropriate for United Taconite would also be 
appropriate for Tilden (and vice versa) because they have similar 
grate-kilns.
(4) Step 4: Evaluate Impacts of Remaining Control Technologies
    There will be an estimated total of 3000 tons per year of 
NOX reductions from the use of the low-stoich technology at 
Tilden and United Taconite. There are no significant costs or 
environmental impacts associated with this technology that would 
necessitate its elimination from consideration as BART.
(5) Step 5: Evaluate Visibility Impacts
    There is about a 16% overall decrease in the amount of 
NOX and SO2 reductions anticipated as a result of 
the control technologies (and resulting emission limits) required by 
this rulemaking, as compared to the 2013 FIP. EPA finds that the 
candidate BART technologies would be expected to achieve substantial 
visibility improvements, although slightly less than what would be 
achieved from the 2013 FIP by an amount roughly corresponding to the 
decrease in emission reductions.
(6) Propose BART
    In EPA's view, the CFD modeling that FCT has conducted provides the 
best currently available evidence as to the NOX emission 
levels that this technology will achieve. According to this modeling 
and engineering reports provided by (the burner manufacturer) Coen, a 
low-stoich burner can be designed to meet 2.8 lbs/MMBtu when burning 
natural gas and 1.5 lbs/MMBtu when burning a gas/coal mix. BART 
requires that the burners be designed to meet these limits and we 
expect that these limits will be met. However, because of the lack of 
experience with these low-stoich burners, including their impact on 
pellet quality, we are proposing to increase the final limits up to 3.0 
lbs/MMBtu when burning natural gas only, and up to 2.5 lbs/MMBtu when 
burning a gas/coal mix if a rigorous demonstration is made that the 2.8 
lbs/MMBtu and 1.5 lbs/MMBtu limits cannot be met.
ii. Hibbing Taconite and ArcelorMittal Minorca Mine Straight-Grate 
Kilns--Five Step BART Evaluation for NOX
(1) Step 1: Identify All Available Retrofit Control Technologies
    As discussed in the August 15, 2012 proposed FIP, the following 
control technologies were identified: external flue gas recirculation, 
low-NOX burners (including both high-stoich and low-stoich), 
induced flue gas recirculation burners, energy efficiency projects, 
ported kilns, and selective catalytic reduction (SCR). Water injection 
in the preheat zone, a pre-combustion approach at the main burners and 
steam injection to the fuel stream were subsequently considered 
technologies.
(2) Step 2: Eliminate Technically Infeasible Options
    External flue gas recirculation and induced flue gas recirculation 
burners were eliminated from consideration because they are technically 
infeasible for the specific application to pellet furnaces due to the 
high oxygen content of the flue gas. Energy efficiency projects were 
eliminated due to the difficulty of assigning a general potential 
emission reduction for this category. EPA agrees that SCR controls are 
infeasible for indurating furnaces based on two SCR vendors declining 
to bid on NOX reduction testing at Minntac.
    In addition, LNBs were eliminated from consideration due to the 
technical challenges associated with their installation and operation 
on the straight-grate kilns at Minorca Mine and Hibbing, which we 
explained in detail in section V above--especially the fact that high-
stoich burners have never been used on any straight-grate kilns. Low-
stoich burners have also been eliminated from consideration because 
they have never been used on straight-grate kilns and also because they 
would be expected to result in higher NOX emissions than the 
technologies being assessed by ArcelorMittal. As described in more 
detail below, water injection in the preheat zone, a pre-combustion 
approach at the main burners, and steam injection to the fuel stream 
are considered to be feasible technologies.
(3) Step 3: Evaluate Control Effectiveness of Remaining Control 
Technologies
    ArcelorMittal has retained engineering firms to assess 
NOX reduction technologies for Minorca's straight-grate 
indurating furnace. The results of this assessment are described in an 
August 11, 2014 report titled ``ArcelorMittal Straight-Grate 
NOX

[[Page 64168]]

Reduction Technology Development Efforts.'' Testing has revealed that 
NOX can be reduced using water injection in the preheat and 
the main burners, although it is significantly more effective at 
reducing NOX in the preheat burners than the main burners. 
Additional options for NOX reduction at straight grate 
furnaces are: pre-combustion optimizations, steam injection, and 
multiple point injection. The viability of these options will be based 
on NOX reduction potential, impacts to pellet quality and 
process, installation and operational downtime, and any energy penalty 
and capital and operating costs.
    Test results have raised the prospect of optimizing NOX 
reductions using both water injection in the preheat zone (where it 
appears more effective) and a pre-combustion approach at the main 
burners. This approach resulted in a 70% or greater reduction on a lbs/
MMBtu basis. Efforts have also been made to evaluate steam injection to 
the fuel stream, which has the potential to provide better mixing in 
the flame zone with increasing NOX reductions where 
distribution concerns exist. Another alternative to reduce 
NOX formation at the main combustion chambers is through a 
number of smaller ``surface spray'' injectors.
    In conclusion, combined modeling indicates that water injection in 
the preheat zone, a pre-combustion approach at the main burners and 
steam injection to the fuel stream technologies can reasonably be 
expected to achieve a 70% NOX reduction on a lbs/MMBtu 
basis. EPA expects these technologies to be equally effective at 
reducing NOX emissions at Hibbing as well as at Minorca 
Mine.
(4) Step 4: Evaluate Impacts of Remaining Control Technologies
    There will be a total estimated 7,400 tons per year of 
NOX reductions from water injection in the preheat zone, a 
pre-combustion approach at the main burners, and steam injection to the 
fuel stream at Minorca Mine and Hibbing. There are no significant costs 
or environmental impacts associated with these control technologies.
(5) Step 5: Evaluate Visibility Impacts
    There is about a 16% overall decrease in the amount of 
NOX and SO2 reductions anticipated as a result of 
the control technologies (and resulting emission limits) required by 
this rulemaking, as compared to the 2013 FIP. EPA finds that the 
candidate BART technologies would be expected to achieve substantial 
visibility improvements, although slightly less than what would be 
achieved from the 2013 FIP by an amount roughly corresponding to the 
decrease in emission reductions.
(6) Propose BART
    Based upon the engineering report prepared for ArcelorMittal in 
which the use of water and steam injection and pre-combustion 
technologies is described, EPA is confident that ArcelorMittal Minorca 
Mine and Hibbing Taconite can meet a limit of 1.2 lbs NOX/
MMBtu. BART requires that these technologies be designed to meet a 
limit of 1.2 lbs/MMBtu and we expect that these limits will be met. 
However, because the particular combination of water and steam 
injection and pre-combustion technologies being considered has not 
previously been used on straight-grate kilns, and there is some 
uncertainty with respect to their effect on pellet quality, we are 
proposing to increase the final limit up to 1.8 lbs/MMBtu if a rigorous 
demonstration is made that the 1.2 lbs/MMBtu limit cannot be met.
iii. United Taconite--Five Step BART Evaluation for SO2
(1) Step 1: Identify All Available Control Technologies
    Flue gas desulfurization (FGD) and use of low sulfur fuels are the 
most appropriate available technologies.
(2) Step 2: Eliminate Technically Infeasible Options
    FGD and use of low sulfur fuels are both technically feasible.
(3) Step 3: Evaluate Control Effectiveness of Remaining Control 
Technologies
    FGD can achieve 90 percent control and the reduction from the use 
of low sulfur fuels varies depending upon the fuel mix and the sulfur 
content of the fuel.
(4) Step 4: Evaluate Impacts of Remaining Control Technologies
    Dry FGD can achieve SO2 reductions of about 3600 tons 
per year from lines 1 and 2. Based upon information supplied by Cliffs 
in its response to comments on the proposed 2013 Taconite FIP, EPA 
subsequently determined the annualized dollars per ton for FGD controls 
to be $5,911/ton for Line 1 and $5,303/ton for Line 2. These cost-
effectiveness values were based upon prior baseline SO2 
emission levels. In light of the reduction in SO2 emissions 
that will result from the use of low-sulfur fuels at United Taconite, 
the cost effectiveness of additional controls has increased to $12,021 
per ton for Line 1 and $7,680 per ton for Line 2. Thus, EPA believes 
that the installation of such controls is not economically feasible.
    United Taconite subsequently proposed an alternate BART definition 
based on burning low sulfur fuels, including increased use of natural 
gas. This alternative will result in about 1,900 tons per year of 
SO2 reductions. There are no other significant impacts or 
costs associated with this alternative.
(5) Step 5: Evaluate Visibility Impacts
    There is about a 16% overall decrease in the amount of 
NOX and SO2 reductions anticipated as a result of 
the control technologies (and resulting emission limits) required by 
this rulemaking, as compared to the 2013 FIP. EPA finds that the 
candidate BART technologies would be expected to achieve substantial 
visibility improvements, although slightly less than what would be 
achieved from the 2013 FIP by an amount roughly corresponding to the 
decrease in emission reductions.
(6) Propose BART
    The proposed BART is based on burning low sulfur fuels, including 
increased use of natural gas, sufficient to meet a Federally 
enforceable aggregate emission limit of 529 lbs SO2/hr, 
based on a 30-day rolling average. This alternative will result in 
about 1900 tons per year of SO2 reductions. In addition to 
the emission limit proposed by Cliffs, to ensure the use of low-sulfur 
fuels and SO2 reductions resulting from the use of low-
sulfur fuels at United Taconite, EPA is also establishing a limitation 
on the coal to be used by requiring the coal have a sulfur content no 
greater than 1.50 percent sulfur by weight based on a monthly block 
average.
    The 529 lbs SO2/hour and 1.5 percent sulfur limit 
constitute BART because of the economic infeasibility of FGD controls 
and also because the facility is not designed to handle lower sulfur 
coal.
iv. Tilden--Five Step BART Evaluation for SO2
(1) Step 1: Identify All Available Control Technologies
    FGD and use of low sulfur fuels are the most appropriate available 
technologies.
(2) Step 2: Eliminate Technically Infeasible Options
    FGD and use of low sulfur fuels are both technically feasible.

[[Page 64169]]

(3) Step 3: Evaluate Control Effectiveness of Remaining Control 
Technologies
    FGD can achieve 90 percent control and the reduction from the use 
of low sulfur fuels varies depending upon the fuel mix and the sulfur 
content of the fuel.
(4) Step 4: Evaluate Impacts of Remaining Control Technologies
    Dry FGD can achieve SO2 reductions of about 1100 tons 
per year from Tilden's line 1. In its September 28, 2012 comments on 
the proposed 2013 Taconite FIP, Cliffs documented dry FGD costs of 
between $11,450 and $15,750 per ton of SO2 removed. These 
costs are not economically reasonable.
    The use of low sulfur fuels, consisting of the use of either 
natural gas or coal with no more than 0.6 percent sulfur, is expected 
to result in a reduction in SO2 emissions of about 300 tons 
per year from baseline conditions. There are no significant costs or 
energy impacts associated with use of these low sulfur fuels.
(5) Step 5: Evaluate Visibility Impacts
    There is about a 16% overall decrease in the amount of 
NOX and SO2 reductions anticipated as a result of 
the control technologies (and resulting emission limits) required by 
this rulemaking, as compared to the 2013 FIP. EPA finds that the 
candidate BART technologies would be expected to achieve substantial 
visibility improvements, although slightly less than what would be 
achieved from the 2013 FIP by an amount roughly corresponding to the 
decrease in emission reductions.
(6) Proposed BART
    BART for SO2 at Tilden's Grate Kiln Line 1 furnace is 
proposed to be met by the use of low sulfur coal and natural gas. 
Beginning six months after the effective date of the rule, 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. This furnace shall 
also meet an initial emission limit of 500 lbs SO2/hr based 
on a 30-day rolling average beginning six months after the effective 
date of the rule. The owner or operator must subsequently calculate a 
permanent lbs SO2/hr mass emission limit based on 12 
continuous months of CEMS emissions data.
    In light of the reduction in SO2 emissions that will 
result from the use of low-sulfur fuels at Tilden, it is expected that 
the dollars per ton of SO2 reduction through FGD would be 
even higher than previously estimated. Thus, EPA believes that the 
installation of such controls is no longer economically reasonable. The 
use of low sulfur fuels is therefore the most viable option and a 0.6 
percent sulfur content represents the use of very low sulfur coal. The 
initial mass limit of 500 lbs/hr is expected to be reduced after 
obtaining a year's worth of CEMS data.

B. Compliance Schedule

    The staggered NOX compliance schedule proposed in this 
action is generally consistent with the schedule in the February 6, 
2013 FIP, as to the number of months to achieve compliance from the 
effective date of the rule. The main differences are that under this 
proposed revised FIP, at Tilden, installation of controls is required 
after 50 months, not the 26 months in the 2013 Taconite FIP, and at 
ArcelorMittal Minorca Mine, installation of controls is required within 
44 months, not 26 months. The following summarizes the dates following 
the effective date of the final action on reconsideration by which EPA 
plans to publish notices making the NOX emission limits 
effective:

Tilden--60 months
Hibbing Line 1--37 months
Hibbing Line 2--55 months
Hibbing Line 3--60 months
United Taconite Line 2--55 months
United Taconite Line 1--37 months
ArcelorMittal--55 months

The staggered schedule is necessary because there is a limited downtime 
each year for each furnace during which the low NOX 
burner(s) can be installed without interfering with production, 
experience gained on the earlier installations can be applied to the 
ones installed later, and installation costs may be spread out.
    The staggered schedule, including additional time at Tilden and 
ArcelorMittal, is even more necessary for the proposed revisions to the 
2013 Taconite FIP because, although the NOX controls that 
are expected to be implemented as a result of the settlement agreement 
and this proposed action have been subject to extensive engineering 
studies, they have not been used on taconite furnaces in the US. There 
will also be an eight month period after installation of controls 
during which emission and pellet quality data will be evaluated and a 
subsequent three month period during which a final emission limit will 
be set by EPA based upon this data. The controls are being designed to 
meet the lower end of the range and it is expected that the limits will 
be set close to the lower end. The actual limit will be based upon the 
UPL statistical test.

C. Averaging Times

    The limits in the 2013 Taconite FIP were expressed in terms of a 
30-day average. A 30-day period in many cases would involve both 
operation with only natural gas and operation with at least some firing 
of coal. EPA prefers to require the companies to meet the limits with a 
coal/gas mix and with only natural gas independently, rather than 
imposing a variable limit computed as a composite of the limits with a 
gas/coal mix and with only natural gas weighted according to time in 
each operating mode. Therefore, EPA is proposing to require separate 
compliance with two limits. One of these limits would govern the 
emissions averaged over 720 successive hours in which the unit burns 
only natural gas. The other limit would govern emissions averaged over 
the 720 successive hours in which the unit burns a gas/coal mix. These 
720-hour rolling average would correspond to a 30-day rolling average, 
as used in the 2013 Taconite FIP, in cases when the fuel use remains 
either natural gas or a gas/coal mix over 30 days. However, a 720-hour 
rolling average ensures that the NOX emission rate will be 
properly compared with the appropriate fuel based limit.
    An example helps illustrate the nature of these limits. Suppose 
that a subject facility burns only natural gas on Days 1-12, burns a 
coal/gas mix on Days 13-16, burns gas again on Days 17-30, does not 
operate on Days 31 and 32, burns gas on Days 33-40, then burns a coal/
gas mix from Days 41-70. This example assumes 24 hours/day operation 
for each operating day. In this case, compliance with the natural gas-
based limit would be determined by dividing total NOX 
emissions by total heat input for the 720 hours on Days 1-12, Days 17-
30, and Days 33-36, as well as on each of the 96 additional sets of 720 
successive hours of burning natural gas up to and including the period 
ending at the end of Day 40. Compliance with the coal or gas/coal mixed 
fuel limit would be determined by dividing total NOX 
emissions by total heat input for the 720 hours on Days 13-16 and Days 
41-66, as well as on each of the 96 additional sets of 720 successive 
hours of burning coal or mixed fuel up to and including the period 
ending at the end of day 70.

D. Procedures for Promulgating Revised FIP Limits

    The regulatory text that follows specifies a process for 
establishing limits to which the identified facilities shall become 
subject. While the text identifies limits that are to apply, the

[[Page 64170]]

text also states that these limits shall become enforceable only after 
EPA publishes notice either confirming these limits or modifying the 
limits within a range that EPA is proposing here to establish. The 
regulatory text also specifies equations that are to be used to 
establish any adjusted limit. Stated more generally, this action is 
proposing not just a final action that will initiate a process to lead 
to establishment of emission limits; today's action is also proposing 
the criteria for determining the level of the ultimate limits and the 
procedure by which these limits are to be made enforceable.
    EPA is proposing for the publication of the final rule to trigger a 
number of subsequent requirements for implementing BART controls on the 
affected taconite plants. Specific dates, defined as a given number of 
months following the effective date of the final rule, are given for 
deadlines for commencing operation of CEMS for NOX and 
SO2, for submitting a report describing planned 
NOX emission controls, for installing the planned 
NOX emission controls, for reporting results of pellet 
quality analyses and simultaneous NOX emission data, for the 
source to submit any report recommending confirmation of modification 
of the emission limit, and for EPA to publish a notice either 
confirming the limit promulgated in 2016 or establishing an alternate 
limit (within a range proposed here). The following summarizes the 
dates following the effective date of the final action on 
reconsideration by which EPA plans to publish notices making the 
NOX emission limits effective:

Tilden--60 months
Hibbing Line 1--37 months
Hibbing Line 2--55 months
Hibbing Line 3--60 months
United Taconite Line 2--55 months
United Taconite Line 1--37 months
ArcelorMittal--55 months

    Based on the above schedule, EPA anticipates publishing a notice 37 
months (addressing 2 units), 55 months (addressing 3 units), and 60 
months (addressing 1 unit) after the effective date of the final rule 
on reconsideration. In each case, the rulemaking will cause a limit to 
become enforceable. EPA is proposing here that the limit will be either 
the limit that is promulgated in the final rule on reconsideration or a 
revised limit. In either case, EPA anticipates that the limit to which 
each unit will ultimately be subject will be in accordance with the 
equations being proposed here, within the upper and lower bounds 
promulgated in the final rule on reconsideration.
    EPA is proposing that these subsequent notices will constitute 
subsequent final actions to this proposal that require no further 
opportunity for public comment. Accordingly, today's notice of proposed 
rulemaking provides 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 for determining control effectiveness, and to 
minimize the time then needed to establish final, enforceable limits. 
Therefore, commenters should provide comments during the comment period 
for today's proposed rulemaking on any issues that might be anticipated 
to arise at any point in the process described in this notice, up to 
and including during the publication of final action as described above 
establishing confirmed or modified limits as fully enforceable.
    The following is an example, based on Hibbing Line 1, of the 
process for setting the final limit. The limits and schedules vary by 
line but the steps are the same for all:
    1. A presumptive limit of 1.2 lbs/MMBtu, based on a 30-day rolling 
average, is established.
    2. The owner or operator must install CEMS within 6 months of the 
effective date of the rule.
    3. After installation of the CEMS, CEMS data must be submitted to 
EPA no later than 30 days from the end of each calendar quarter until 
34 months from the effective date of the rule.
    4. Within 24 months of the effective date a final report must be 
submitted to EPA containing a detailed engineering analysis and 
modeling of the NOX reduction technology (which must be 
designed to meet 1.2 lbs/MMBtu) being installed.
    5. The NOX reduction control technology must be 
installed no later than 26 months after the effective date of the rule.
    6. Within the earlier of 6 months of the installation of the 
NOX reduction control technology or 26 months from the 
effective date of the rule the results of pellet quality analyses must 
be provided to EPA no later than 30 days from the end of each calendar 
quarter pellet quality analyses must be provided to EPA until 34 months 
from the effective date of the rule. For each pellet quality analysis 
factor, e.g. compression and reducibilty, the following must be 
provided: (a) The defined acceptable range for each factor as contained 
in Hibbing's ISO 9001 quality management system, and (b) pellet quality 
testing results that state the date and time when pellets were produced 
outside of the defined acceptable range for the indicated pellet 
quality factors.
    7. No later than 34 months after the effective date of the rule, a 
report may be submitted to EPA either confirming the 1.2 lbs/MMBtu 
presumptive limit or requesting a modification of the limit up to the 
upper end of the range (1.8 lbs/MMBtu in this case).
    8. The final limit will be based on the CEMS data from the eight 
month period from the end of month 26 to the end of month 34, excluding 
any time in which the pellet quality standards are not met. The final 
limit will be based upon the 95 percent upper predictive limit (UPL). 
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. For 
example, the 95 percent UPL value is the emission level that the source 
would be predicted to be below during 95 out of 100 hourly intervals. 
The UPL is calculated using an equation based on the average and 
variance of a data set, the distribution of the data, and quantity of 
data points.
    9. 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 the effective date of the rule.

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    This proposed action is not a ``significant regulatory action'' 
under the terms of Executive Order 12866 (58 FR 51735, October 4, 1993) 
and is therefore not subject to review under Executive Orders 12866 and 
13563 (76 FR 3821, January 21, 2011). As discussed in detail in section 
VI. C below, the proposed FIP applies to only four sources. It is 
therefore not a rule of general applicability.

B. Paperwork Reduction Act

    This proposed action does not impose an information collection 
burden under the provisions of the Paperwork Reduction Act, 44 U.S.C. 
3501 et seq. Under the Paperwork Reduction Act, a ``collection of 
information'' is defined as a requirement for ``answers to . . .

[[Page 64171]]

identical reporting or recordkeeping requirements imposed on ten or 
more persons . . . .'' 44 U.S.C. 3502(3)(A). Because the proposed FIP 
applies to just six facilities, the Paperwork Reduction Act does not 
apply. See 5 CFR 1320(c).
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid Office of Management and Budget (OMB) control number. 
The OMB control numbers for our regulations in 40 CFR are listed in 40 
CFR part 9.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to prepare a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements under the Administrative 
Procedure Act or any other statute unless the agency certifies that the 
rule will not have a significant economic impact on a substantial 
number of small entities. Small entities include small businesses, 
small organizations, and small governmental jurisdictions.
    For purposes of assessing the impacts of today's proposed rule on 
small entities, small entity is defined as: (1) A small business as 
defined by the Small Business Administration's (SBA) regulations at 13 
CFR 121.201; (2) a small governmental jurisdiction that is a government 
of a city, county, town, school district or special district with a 
population of less than 50,000; and (3) a small organization that is 
any not-for-profit enterprise which is independently owned and operated 
and is not dominant in its field.
    After considering the economic impacts of this proposed action on 
small entities, I certify that this proposed action will not have a 
significant economic impact on a substantial number of small entities. 
EPA's proposal adds additional controls to certain sources. The 
Regional Haze FIP that EPA is proposing for purposes of the regional 
haze program consists of imposing 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 proposing emission controls 
on the indurating furnaces at four taconite facilities and none of 
these sources are owned by small entities, and therefore are not small 
entities.

D. Unfunded Mandates Reform Act (UMRA)

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and Tribal 
governments and the private sector. Under section 202 of UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and Tribal governments, in 
the aggregate, or to the private sector, of $100 million or more 
(adjusted for inflation) in any one year. Before promulgating an EPA 
rule for which a written statement is needed, section 205 of UMRA 
generally requires EPA to identify and consider a reasonable number of 
regulatory alternatives and adopt the least costly, most cost-
effective, or least burdensome alternative that achieves the objectives 
of the rule. The provisions of section 205 of UMRA do not apply when 
they are inconsistent with applicable law. Moreover, section 205 of 
UMRA allows EPA to adopt an alternative other than the least costly, 
most cost-effective, or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including Tribal governments, it must have developed under 
section 203 of UMRA a small government agency plan. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments to have meaningful and timely 
input in the development of EPA regulatory proposals with significant 
Federal intergovernmental mandates, and informing, educating, and 
advising small governments on compliance with the regulatory 
requirements.
    Under Title II of UMRA, EPA has determined that this proposed rule 
does not contain a Federal mandate that may result in expenditures that 
exceed the inflation-adjusted UMRA threshold of $100 million by State, 
local, or Tribal governments or the private sector in any one year. In 
addition, this proposed rule does not contain a significant Federal 
intergovernmental mandate as described by section 203 of UMRA nor does 
it contain any regulatory requirements that might significantly or 
uniquely affect small governments.

E. Executive Order 13132: Federalism

    Federalism (64 FR 43255, August 10, 1999) revokes and replaces 
Executive Orders 12612 (Federalism) and 12875 (Enhancing the 
Intergovernmental Partnership). Executive Order 13132 requires EPA to 
develop an accountable process to ensure ``meaningful and timely input 
by State and local officials in the development of regulatory policies 
that have federalism implications.'' ``Policies that have federalism 
implications'' is defined in the Executive Order to include regulations 
that 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.'' Under Executive Order 13132, EPA may not issue a 
regulation that has federalism implications, that imposes substantial 
direct compliance costs, and that is not required by statute, unless 
the Federal government provides the funds necessary to pay the direct 
compliance costs incurred by State and local governments, or EPA 
consults with State and local officials early in the process of 
developing the proposed regulation. EPA also may not issue a regulation 
that has federalism implications and that preempts State law unless the 
Agency consults with State and local officials early in the process of 
developing the proposed regulation.
    This rule will not have substantial direct effects on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government, as specified in Executive Order 13132, because it 
merely addresses the State not fully meeting its obligation to prohibit 
emissions from interfering with other states measures to protect 
visibility established in the CAA. Thus, Executive Order 13132 does not 
apply to this action. In the spirit of Executive Order 13132, and 
consistent with EPA policy to promote communications between EPA and 
State and local governments,

[[Page 64172]]

EPA specifically solicits comment on this proposed rule from State and 
local officials.

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

    Executive Order 13175, entitled Consultation and Coordination with 
Indian Tribal Governments (65 FR 67249, November 9, 2000), requires EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by tribal officials in the development of regulatory policies 
that have tribal implications.'' This proposed rule 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 in a June 28 conference call with the Michigan and Minnesota 
Tribes.

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

    Executive Order 13045: Protection of Children from Environmental 
Health Risks and Safety Risks (62 FR 19885, April 23, 1997), applies to 
any rule that: (1) Is determined to be economically significant as 
defined under Executive Order 12866; and (2) concerns an environmental 
health or safety risk that we have reason to believe may have a 
disproportionate effect on children. EPA interprets EO 13045 as 
applying only to those regulatory actions that concern health or safety 
risks, such that the analysis required under section 5-501 of the EO 
has the potential to influence the regulation. This action is not 
subject to EO 13045 because it does not establish an environmental 
standard intended to mitigate health or safety risks. This proposed 
action addresses regional haze and visibility protection. Further, 
because this proposed amendment to the current regulation will require 
controls that will cost an amount equal to or less than the cost of 
controls required under the current regulation, it is not an 
economically significant regulatory action. However, to the extent this 
proposed rule will limit emissions of NOX, SO2, 
and PM, 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 (66 FR 28355 
(May 22, 2001)), because it is not a significant regulatory action 
under Executive Order 12866.

I. National Technology Transfer and Advancement Act

    Section 12 of the National Technology Transfer and Advancement Act 
(NTTAA) of 1995 requires Federal agencies to evaluate existing 
technical standards when developing a new regulation. To comply with 
NTTAA, EPA must consider and use ``voluntary consensus standards'' 
(VCS) if available and applicable when developing programs and policies 
unless doing so would be inconsistent with applicable law or otherwise 
impractical.
    VCS are inapplicable to this action because application of those 
requirements would be inconsistent with the CAA.

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

    Executive Order 12898 (59 FR 7629, February 16, 1994), establishes 
Federal executive policy on environmental justice. Its main provision 
directs Federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the United States.
    We have determined that this proposed rule, if finalized, 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.

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, 
Volatile organic compounds.

    Dated: September 8, 2015.
Susan Hedman
Regional Administrator, Region 5.
    40 CFR part 52 is proposed to be 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 (o) 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 
[EFFECTIVE DATE OF FINAL RULE] and only after EPA's confirmation or 
modification of the emission limit in accordance with the procedures 
set forth below.
    (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 [EFFECTIVE DATE OF FINAL RULE] 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 
[EFFECTIVE DATE OF FINAL RULE], that doesn't fall within a calendar 
quarter, must be submitted to EPA no later than 7 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 
[EFFECTIVE DATE OF FINAL RULE].
    (iii) No later than 48 months from [EFFECTIVE DATE OF FINAL RULE], 
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

[[Page 64173]]

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 the effective date of the rule.
    (v) Commencing on the earlier of:
    (A) Six months from the installation of the NOX 
reduction control technology; or
    (B) 50 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. 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 seven 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 [EFFECTIVE DATE OF FINAL RULE], 
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 (o) 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 (o) 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 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 [EFFECTIVE DATE OF FINAL 
RULE]. 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 [EFFECTIVE DATE OF FINAL RULE].
    (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 [EFFECTIVE DATE OF 
FINAL RULE]. Compliance with these emission limits shall be 
demonstrated with data collected by a CEMS for SO2. The 
owner or operator must start collecting CEMS data for SO2 
beginning six months after [EFFECTIVE DATE OF FINAL RULE] 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 6 months after [EFFECTIVE DATE OF FINAL 
RULE], 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 twelve continuous months of CEMS emissions data and 
submit such limit, calculations, and CEMS data to EPA no later than 36 
months after [EFFECTIVE DATE OF FINAL RULE]. If the submitted CEMS 
SO2 hourly data is normally distributed, the SO2 
lbs/hr emission rate shall be 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 is not normally distributed, the SO2 lbs/hr

[[Page 64174]]

emission rate shall be based on the non-parametric equation provided in 
paragraph (o) of this section. Compliance to 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 [EFFECTIVE DATE OF FINAL RULE]. EPA may 
adjust the 500 lbs/hr SO2 limit downward to reflect the 
calculated SO2 emission rate; however, EPA will not increase 
the SO2 limit above 500 lbs/hr.
    (4) Starting 26 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE], 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 
regulation 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 [EFFECTIVE DATE OF 
FINAL RULE]. All CEMS associated with monitoring SO2 must be 
installed and operational no later than six months after [EFFECTIVE 
DATE OF FINAL RULE]. 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 fifteen-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 which fuel is combusted in the BART affected Unit regardless of 
whether

[[Page 64175]]

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 
5 years following the date of creation.
    (iii) Records must be kept on site for at least 2 years following 
the date of creation and may be kept offsite, but readily accessible, 
for the remaining 3 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 (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.
    (iii) A notification of the date the construction of control 
devices and

[[Page 64176]]

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 startup date for control devices and 
burners installed as a result of this section postmarked no later than 
30 days after the startup date.
    (vi) A notification of the startup date for 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, 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 (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 three-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)-
(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,

[[Page 64177]]

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 paragraphs (n)(7)(x)(C) of this section.
    (A) For purposes of 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 at (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 
paragraph (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)-(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.

[[Page 64178]]

    (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 is 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 shows 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.
    (o) Equations for Establishing the Upper Predictive Limit
    (1) Equation for Normal Distribution and Statistically Independent 
Data
[GRAPHIC] [TIFF OMITTED] TP22OC15.001

Where:
x = average or mean of 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 dataset;
n = number of values
m = number of values used to calculate the test average (m = 720 as 
per averaging time)

    (2)(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] TP22OC15.002

[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)

    (3) If data are dependent then use the following equation.
    Equation for Normal Distribution and Data not Statistically 
Independent
[GRAPHIC] [TIFF OMITTED] TP22OC15.003

Where:
[rho] = correlation between data points

    (4) Non-parametric Equations for Data Not Normally Distributed

m = (n + 1) * [alpha]
m = the rank of the ordered data point, when data is sorted smallest 
to largest
n = number of data points
[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 is 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.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 proposed to be 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.

    (a) [Reserved]
    (b)(1) NOX emission limits.
    (i) * * *
    (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 [EFFECTIVE DATE OF FINAL RULE] and only after EPA's confirmation 
or modification of the emission limit in accordance with the procedures 
set forth below.
    (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 the 
effective date of the rule. 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 [EFFECTIVE DATE 
OF FINAL RULE], that doesn't fall within a calendar quarter, must be

[[Page 64179]]

submitted to EPA no later than seven 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 the effective date 
of the rule.
    (3) No later than 24 months after [EFFECTIVE DATE OF FINAL RULE] 
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 
[EFFECTIVE DATE OF FINAL RULE].
    (5) Commencing on the earlier of:
    (i) Six months from the installation of the NOX 
reduction control technology; or
    (ii) 26 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. Any remaining 
results through the end of the 34th month from [EFFECTIVE DATE OF FINAL 
RULE], that do not fall within a calendar quarter, must be submitted to 
EPA no later than seven 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, 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 [EFFECTIVE DATE OF FINAL RULE], 
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 [EFFECTIVE DATE OF FINAL RULE]. 
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 [EFFECTIVE DATE OF FINAL RULE] and only after EPA's confirmation 
or modification of the emission limit in accordance with the procedures 
set forth below.
    (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 
[EFFECTIVE DATE OF FINAL RULE]. 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 [EFFECTIVE 
DATE OF FINAL RULE], that doesn't fall within a calendar quarter, must 
be submitted to EPA no later than seven 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 [EFFECTIVE DATE OF 
FINAL RULE].
    (3) No later than 42 months after [EFFECTIVE DATE OF FINAL RULE] 
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.

[[Page 64180]]

    (4) The NOX reduction control technology shall be 
installed on Hibbing Line 2 furnace no later than 44 months after 
[EFFECTIVE DATE OF FINAL RULE].
    (5) Commencing on the earlier of:
    (i) Six months from the installation of the NOX 
reduction control technology; or
    (ii) 44 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. Any remaining 
results through the end of the 52nd month from [EFFECTIVE DATE OF FINAL 
RULE], that do not fall within a calendar quarter, must be submitted to 
EPA no later than seven 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 [EFFECTIVE DATE OF FINAL RULE], 
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 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 [EFFECTIVE DATE OF FINAL RULE]. 
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 [EFFECTIVE DATE OF FINAL RULE] and only after EPA's confirmation 
or modification of the emission limit in accordance with the procedures 
set forth below.
    (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 
[EFFECTIVE DATE OF FINAL RULE]. 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 [EFFECTIVE 
DATE OF FINAL RULE], that doesn't fall within a calendar quarter, must 
be submitted to EPA no later than seven 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 the effective date 
of the rule.
    (3) No later than 48 months after [EFFECTIVE DATE OF FINAL RULE] 
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 
[EFFECTIVE DATE OF FINAL RULE].
    (5) Commencing on the earlier of:
    (i) Six months from the installation of the NOX 
reduction control technology; or
    (ii) 50 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. Any remaining 
results through the end of the 57th month from [EFFECTIVE DATE OF FINAL 
RULE], that do not fall within a calendar quarter, must be submitted to 
EPA no later than seven 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

[[Page 64181]]

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 [EFFECTIVE DATE OF FINAL RULE], 
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 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 [EFFECTIVE DATE OF FINAL RULE]. 
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 [EFFECTIVE DATE OF FINAL RULE] and only after EPA's 
confirmation or modification of the emission limit in accordance with 
the procedures set forth below.
    (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 upon [EFFECTIVE DATE OF FINAL RULE] 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 
[EFFECTIVE DATE OF FINAL RULE], that doesn't fall within a calendar 
quarter, must be submitted to EPA no later than 7 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 
[EFFECTIVE DATE OF FINAL RULE].
    (3) No later than 24 months from [EFFECTIVE DATE OF FINAL RULE], 
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 [EFFECTIVE DATE OF FINAL RULE].
    (5) Commencing on the earlier of
    (i) Six months from the installation of the NOX 
reduction control technology; or
    (ii) 26 months from the effective date of the rule, 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 [EFFECTIVE DATE OF FINAL RULE]. 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 seven 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 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

[[Page 64182]]

to EPA as Confidential Business Information.
    (6) No later than 34 months after [EFFECTIVE DATE OF FINAL RULE], 
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 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 [EFFECTIVE DATE OF FINAL 
RULE]. 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 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 [EFFECTIVE DATE OF FINAL RULE].
(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 [EFFECTIVE DATE OF FINAL RULE] and only after EPA's 
confirmation or modification of the emission limit in accordance with 
the procedures set forth below.
    (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 upon [EFFECTIVE DATE OF FINAL RULE] 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 
[EFFECTIVE DATE OF FINAL RULE], that doesn't fall within a calendar 
quarter, must be submitted to EPA no later than 7 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 
[EFFECTIVE DATE OF FINAL RULE].
    (3) No later than 42 months from [EFFECTIVE DATE OF FINAL RULE], 
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 the effective date of the rule.
    (5) Commencing on the earlier of:
    (i) Six months from the installation of the NOX 
reduction control technology; or
    (ii) 44 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. 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 seven 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 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.
    (6) No later than 52 months after [EFFECTIVE DATE OF FINAL RULE], 
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

[[Page 64183]]

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 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 [EFFECTIVE DATE OF FINAL 
RULE]. 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 [EFFECTIVE DATE OF FINAL RULE].
    (v) ArcelorMittal Minorca Mine
    (A) 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 [EFFECTIVE DATE OF FINAL RULE] and 
only after EPA's confirmation or modification of the emission limit in 
accordance with the procedures set forth below.
    (B) 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 [EFFECTIVE DATE OF FINAL RULE]. 
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 [EFFECTIVE DATE OF FINAL RULE], that doesn't fall 
within a calendar quarter, must be submitted to EPA no later than seven 
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 [EFFECTIVE DATE OF FINAL RULE].
    (C) No later than 42 months after [EFFECTIVE DATE OF FINAL RULE] 
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.
    (D) The NOX reduction control technology shall be 
installed on the ArcelorMittal Minorca Mine indurating furnace no later 
than 44 months after the effective date of the rule.
    (E) Commencing on the earlier of:
    (1) Six months from the installation of the NOX 
reduction control technology; or
    (2) 44 months from [EFFECTIVE DATE OF FINAL RULE], 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 [EFFECTIVE DATE OF FINAL RULE]. Any remaining 
results through the end of the 52nd month from [EFFECTIVE DATE OF FINAL 
RULE], that do not fall within a calendar quarter, must be submitted to 
EPA no later than seven 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.
    (F) No later than 52 months after [EFFECTIVE DATE OF FINAL RULE], 
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/

[[Page 64184]]

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)(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.
    (G) 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 [EFFECTIVE DATE OF FINAL RULE]. 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.
* * * * *
    (2) SO2 emission limits
* * * * *
    (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 
[EFFECTIVE DATE OF FINAL RULE] the effective date of the rule. 
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 [EFFECTIVE DATE OF 
FINAL RULE] and submit the data to EPA no later than 30 days from the 
end of each calendar quarter. Beginning 6 months after the effective 
date of the rule, 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 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)-(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 March 8, 2013.
    (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 [EFFECTIVE DATE OF FINAL RULE].
    (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

[[Page 64185]]

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 fifteen-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)-(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 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 5 
hours during a 24-hour period, then the actual operating hours for that 
day are 5. 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)-(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 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 
5 years following the date of creation.
    (iii) Records must be kept on site for at least 2 years following 
the date of creation and may be kept offsite, but readily accessible, 
for the remaining 3 years.
    (2) The owner or operator of the BART affected units must maintain 
the records at paragraphs (d)(2)(i)-(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,

[[Page 64186]]

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)-(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 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)-(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

[[Page 64187]]

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.
    (x) A table summarizing the total duration of excess emissions, as 
defined at paragraphs (e)(7)(x)(A) to (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 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 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

[[Page 64188]]

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 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 is 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 shows 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] TP22OC15.004

Where:

x = average or mean of 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)
s2 = variance of the dataset;
n = number of values
m = number of values used to calculate the test average (m = 720 as 
per averaging time)

    (2)(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] TP22OC15.005


[[Page 64189]]


[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)

    (3) If data are dependent then use the following equation.
    Equation for Normal Distribution and Data not Statistically 
Independent
[GRAPHIC] [TIFF OMITTED] TP22OC15.006

Where:
[rho] = correlation between data points

    (4) Non-parametric Equations for Data Not Normally Distributed

m = (n + 1) * [alpha]

m = the rank of the ordered data point, when data is sorted smallest 
to largest
n = number of data points
[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 is 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 = xmimd = 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. 2015-25023 Filed 10-21-15; 8:45 am]
BILLING CODE 6560-50-P