Document ID: EPA-R05-OAR-2010-0037-0083
Agency: epa
Document Type: Proposed Rule
Title: Proposed Disapproval of Regional Haze BART for Taconite Plants in Michigan and Minnesota
Posted Date: 2013-02-06T05:00Z

[Federal Register Volume 78, Number 25 (Wednesday, February 6, 2013)]
[Proposed Rules]
[Pages 8478-8485]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-01463]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R05-OAR-2010-0954 and EPA-R05-OAR-2010-0037; FRL-9772-8]

Approval and Promulgation of Air Quality Implementation Plans; 
States of Michigan and Minnesota; Regional Haze

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule; supplemental.

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SUMMARY: In this supplemental notice of proposed rulemaking, EPA is 
soliciting additional comments on its proposal to disapprove in part 
the Michigan and Minnesota regional haze State Implementation Plans 
(SIPs) for failure to mandate best available retrofit technology (BART) 
for taconite facilities within these states. This proposal supplements 
an August 15,2012, action that proposed to disapprove these elements of 
these SIPs and to establish

[[Page 8479]]

Federal emission limits representing BART.

DATES: Comments must be received on or before March 8, 2013.

ADDRESSES: Submit your comments, identified by Docket IDs No. EPA-R05-
OAR-2010-0954 and EPA-R05-OAR-2010-0037, by one of the following 
methods:
    1. www.regulations.gov: Follow the on-line instructions for 
submitting comments.
    2. Email: aburano.douglas@epa.gov.
    3. Fax: (312) 692-2450.
    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 IDs No. EPA-R05-OAR-
2010-0954 and EPA-R05-OAR-2010-0037. 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 John Summerhays at (312) 886-6067 
before visiting the Region 5 office.

FOR FURTHER INFORMATION CONTACT: John Summerhays, Environmental 
Scientist, Attainment Planning and Maintenance Section, Air Programs 
Branch (AR-18J), Environmental Protection Agency, Region 5, 77 West 
Jackson Boulevard, Chicago, Illinois 60604, (312) 886-6067, 
summerhays.john@epa.gov.

SUPPLEMENTARY INFORMATION: This supplementary information section is 
arranged as follows:

I. What should I consider as I prepare my comments for EPA?
II. What is the background for this action?
III. What is EPA's review of Minnesota and Michigan's BART 
determinations for taconite facilities?
    A. Minnesota
    B. Michigan
IV. How does this action relate to the action to promulgate Federal 
requirements for taconite plants?
V. 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--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 is the background for this action?

    Minnesota submitted its regional haze plan on December 30, 2009, 
and further submitted a proposed supplemental submission on January 5, 
2012, and a final supplemental submission on May 8, 2012. EPA proposed 
approval of the Minnesota plan on January 25, 2012 (77 FR 3681). Among 
other actions, this proposed rule proposed to approve Minnesota's plan 
as requiring BART for the State's several taconite plants, provided 
Minnesota submitted its proposed taconite plant BART limits prior to 
final EPA action. However, comments on Minnesota's and EPA's proposals 
provided evidence that better, cost-effective technology for control of 
taconite plant emissions was available. Therefore, EPA published a 
final rule approving other aspects of the Minnesota regional haze plan 
on June 12, 2012 (77 FR 34801), but deferred action on BART for 
Minnesota's taconite facilities.
    Michigan submitted its regional haze plan on November 5, 2010. EPA 
proposed action on the Michigan regional haze plan on August 6, 2012 
(77 FR 46912). This proposed rule proposed to approve several aspects 
of Michigan's regional haze plan, and proposed to disapprove Michigan's 
BART determinations for a Portland cement plant and a paper mill and 
proposed Federal limits for those two facilities. However, in this 
proposed rule, EPA deferred action on BART for the Tilden Mining 
taconite facility in Michigan. EPA published final action pursuant to 
this proposal on December 3, 2012 (77 FR 71533), again deferring action 
on BART for the Tilden Mining taconite plant in Michigan.
    Michigan has a second taconite plant, known as Empire Mining. While 
Empire Mining began operation during the statutory timeframe such that 
the

[[Page 8480]]

facility is BART-eligible, Michigan's plan demonstrates satisfactorily 
that the impact of this facility is sufficiently small, as a result of 
the enforceable shutdown of one line, that the facility may justifiably 
be exempted from the BART requirement. On the other hand, Michigan's 
plan identifies Tilden Mining as meeting the criteria for being subject 
to BART. Thus, references in this action to taconite plants in 
Minnesota and Michigan are meant to refer only to taconite plants in 
Minnesota and Michigan that are subject to BART, which includes all of 
the taconite plants in Minnesota and Tilden Mining in Michigan but does 
not include the Empire Mining plant.
    On August 15, 2012 (77 FR 49308), EPA published proposed action on 
BART for taconite plants in Minnesota and Michigan. In that action, EPA 
reviewed relevant information regarding the feasibility of various 
options for the control of emissions from taconite plants and reviewed 
other information relevant to determining BART for these plants.
    Based on this review and the availability of cost-effective 
controls, EPA proposed Federal emission limits requiring more stringent 
control of emissions of nitrogen oxides (NOX) and sulfur 
dioxide (SO2) than had been required by Minnesota or 
Michigan. The notice of proposed rulemaking proposing these limits 
provided a full discussion of why EPA proposed to conclude that proper 
consideration of the BART criteria resulted in more stringent control 
than was required by the States, thus implicitly concluding that the 
state submittals did not require controls representing BART. 
Furthermore, the action proposed regulatory text stating that the state 
submittals failed to require BART for the taconite plants.
    Nevertheless, EPA is publishing this supplemental notice of 
proposed rulemaking to provide additional information regarding the 
agency's views on Minnesota's and Michigan's plans and to solicit 
additional comment regarding the proposal to disapprove in part the 
plans for failing to require BART at the applicable taconite plants. 
EPA is not soliciting further comment on its proposed Federal limits; 
this action only addresses whether the state plans must be disapproved 
for failing to provide proper analysis and require BART for applicable 
taconite plants. Further discussion regarding the relationship between 
this action and the action published August 15, 2012 is provided below.
    Previous notices of proposed rulemaking addressing the States' 
plans, i.e., the actions published January 25, 2012, and August 6, 
2012, for Minnesota and Michigan, respectively, include substantial 
discussion of the requirements under sections 169A and 169B of the 
Clean Air Act and subpart P of 40 CFR 50 for regional haze plans. Most 
pertinent to today's action are the requirements for BART in Clean Air 
Act section 169A and 40 CFR 51.308(e). In making BART determinations, 
section 169A(g)(2) of the Clean Air Act requires the state to consider 
the following factors: (1) The costs of compliance; (2) the energy and 
non-air quality environmental impacts of compliance; (3) any existing 
pollution control technology in use at the source; (4) the remaining 
useful life of the source; and (5) the degree of improvement in 
visibility which may reasonably be anticipated to result from the use 
of such technology.

III. What is EPA's review of Minnesota and Michigan's BART 
determinations for taconite facilities?

A. Minnesota

    In its December 30, 2009, regional haze SIP submittal, Minnesota 
identified the types of controls that it determined to represent BART 
for its taconite plants. In all cases, good combustion practice was 
determined to represent BART with respect to the control of 
NOX, existing controls were determined to represent BART for 
the control of SO2, and the maximum achievable control 
technology limits in 40 CFR part 63 subpart RRRRR were determined to 
represent BART for the control of particulate matter. However, this 
submittal included no enforceable emission limits to require emissions 
control at these facilities.
    To remedy this deficiency, Minnesota proposed emission limits 
nominally representing good combustion practice for these facilities on 
December 19, 2011. EPA provided comments on this proposal, stating that 
more stringent limits were warranted and necessary because 
``information supporting low NOX main burners as BART is 
well documented and has been available for some time.'' See letter 
dated February 10, 2012, signed by Douglas Aburano. These comments 
provided a timetable showing that an analysis in January 2009 of 
measures for reducing NOX emissions at U.S. Steel's Minntac 
Iron Ore Pelletizing Plant recommended pursuing use of low 
NOX main burners. Initial tests were sufficiently successful 
that a report on these efforts, issued on April 13, 2010, recommended 
further testing. Then, U.S. Steel submitted a report to Minnesota on 
October 22, 2010, with test results from Minntac's Line 7 that 
indicated that a 70 percent reduction in NOX emissions was 
achievable via a low NOX main burner. U.S. Steel reported 
similar results for Minntac Line 6 to Minnesota on December 1, 2011.
    Nevertheless, Minnesota's submittal did not demonstrate requisite 
consideration of this evidence regarding the availability and 
feasibility of this more effective control technology. In 2008, the 
owners of each taconite facility asserted that a low NOX 
main burner was infeasible. Minnesota, in its December 2009 SIP 
submittal summarily concurred with the facilities, and the State in its 
May 2012 submittal did not reconsider the feasibility of this control 
option.
    EPA's BART Guidelines identify a five-step process for conducting a 
BART analysis, step two of which is to determine whether the available 
options identified in step one are technically feasible. The state 
``should document a demonstration of technical infeasibility and should 
explain, based on physical, chemical, or engineering principles, why 
technical difficulties would preclude the successful use of the control 
option on the emissions unit under review.'' See Section IV Step 2 of 
the BART Guidelines, also at 70 FR 39163. Minnesota provided no such 
demonstration and included no explanation why this control option 
should be considered infeasible. Beyond lacking any discussion of 
relevant principles bearing on whether the feasibility of low 
NOX burners in other industries suggests that low 
NOX main burners are feasible for taconite facilities, 
Minnesota's submittals do not discuss the successful demonstration of 
this control option at U.S. Steel's facilities or explain why this 
control option should not be considered feasible at these plants and at 
the other Minnesota taconite plants. Since Minnesota improperly 
considered low NOX main burners to be infeasible, the 
State's plan lacked the necessary analysis of the costs, emission 
reductions, visibility benefits, and other relevant information to 
determine whether these controls represent BART. Instead, in its May 
2012 submittal, Minnesota stated ``The [Minnesota Pollution Control 
Agency (MPCA)] understood the purpose of the Supplemental SIP was to 
establish emission limits that correspond to the previously determined 
BART technology. The MPCA does not believe that completing the emission 
limits is a vehicle for completely re-evaluating the BART 
determinations for the taconite facilities.'' Minnesota conceded that 
the

[[Page 8481]]

tests at Minntac ``indicate a potential to reach a 70 percent reduction 
in NOX emissions at the subject lines [under certain 
conditions],'' but Minnesota characterized the tests as ``pilot tests'' 
that could not be used without substantial additional effort to 
establish appropriate BART limits. See the 279th page of the Minnesota 
document entitled ``Regional Haze State Implementation Plan Supplement 
April 2012.''
    EPA has several objections to Minnesota's rationale for failing to 
require low NOX burners as BART for its taconite plants. 
When EPA proposes an action but then receives significant evidence 
favoring an alternate action, EPA must consider that evidence and take 
the alternate action if warranted. See Sierra Club v. EPA, 671 F.3d 955 
(9th Cir. 2012). Although EPA initially proposed to approve Minnesota's 
taconite limits, EPA then received evidence that disapproval was 
warranted because more effective controls were available. EPA's 
consideration of this evidence resulted in EPA's August 15, 2012, 
proposal to disapprove in part Minnesota's regional haze plan with 
respect to BART for taconite plants and in EPA's action today to 
publish this supplemental notice of proposed rulemaking.
    EPA believes that Minnesota is under similar obligation to 
reconsider its taconite plant BART limits. The State solicited comments 
regarding the limits it proposed to establish for its taconite plants, 
the State received comments demonstrating that significantly tighter 
limits were warranted, and the State did not give due consideration to 
those comments. The failure to promulgate limits reflecting low 
NOX main burners is especially problematic for Minntac, 
where the benefits of this technology had been physically demonstrated. 
Minnesota also did not give due consideration to the evidence that 
similar technology could be expected to achieve similar emission 
reductions and benefits at other Minnesota taconite plants.
    Furthermore, even at the time Minnesota submitted its original 
regional haze SIP (December 2009), information was available that low 
NOX main burners, which had been successfully demonstrated 
in several other industries, were likely to be a successful technology 
for reducing NOX emissions from taconite facilities as well. 
Although EPA did not have the relevant information when it published 
its January 2012 proposed rulemaking, the above chronology suggests 
that Minnesota had information even in 2009 that warranted considering 
low NOX main burners to be a feasible technology.
    The requirements in Minnesota's final submittal also reflect 
significant modifications from the control technology that the State 
determined in 2009 to reflect BART. Minnesota determined in 2009 that 
good combustion practice represented BART. However, aside from 
requiring continuation of the heat recuperation project at the Hibbing 
Taconite Plant, Minnesota's final submittal provided no evidence that 
good combustion practice is actually required. Minnesota did not 
explain what specific measures constitute good combustion practice, 
stating only that good combustion practice varies from plant to plant. 
However, Minnesota did not define good combustion practice either in 
general or on a plant-by-plant basis.
    Minnesota determined emission limits by conducting statistical 
analyses of full sets of recent emissions data measured at the taconite 
plants. While existing emissions may in some cases reflect some good 
combustion practices, Minnesota did not differentiate whether any 
particular data did or did not represent application of good combustion 
practice. Thus, Minnesota's limits must be considered to represent 
simply the existing combustion practice in effect during the testing, 
without regard to whether these limits reflect application of good 
combustion practices. Because the companies were required to collect 
these data for purposes of determining these limits, with instructions 
to operate under worst case conditions, it is reasonable to conclude 
that the companies would not have employed good combustion practices, 
as those would not have created ``worst case conditions.''
    Further, Minnesota's submittal did not determine whether good 
combustion practices beyond those currently being implemented are 
feasible, either in general or on a plant-specific basis. Minnesota's 
December 2009 submittal determined that BART would be good combustion 
practice, suggesting that BART would reflect identification, 
evaluation, and implementation of improvements in combustion practice. 
However, Minnesota's final submittal lacks any such identification, 
evaluation, or requirement for any such improvement in combustion 
practice. Moreover, the submittal does not evaluate whether current 
combustion practice (or, more precisely, the combustion practice in 
place during collection of the pertinent emissions data) represents 
good combustion practice. In these respects, while Minnesota's December 
2009 submittal determined BART for NOX to be good combustion 
practice, Minnesota's final submittal contained no provisions ensuring 
that good combustion practice will actually be followed.
    Minnesota's final submittal also deviates in other significant 
respects from its December 2009 submittal. Minnesota's final submittal 
relies on the Cross-State Air Pollution Rule to satisfy the BART 
requirement for most of the State's electric generating units, whereas 
its December 2009 plan determines BART on a plant-by-plant basis. The 
long-term strategy in Minnesota's final plan provides for taconite 
plants to conduct modeling and to recommend emission limits that would 
provide for attainment of the nitrogen dioxide (NO2) and 
SO2 air quality standards, whereas the December 2009 plan 
provides for the companies to conduct pilot testing of emission control 
technology. EPA is not conducting rulemaking here on these features of 
Minnesota's regional haze plan, but these changes demonstrate that 
Minnesota recognized its latitude to update portions of its December 
2009 submittal significantly in light of more recent information. 
Similarly, Minnesota cannot argue that it was obligated to set limits 
based on its December 2009 BART determination, in the face of evidence 
that more effective control is available.
    EPA is also concerned that Minnesota rejected flue gas 
desulfurization as a feasible option for control of SO2 
emissions at United Taconite (UTac). At this facility, Minnesota made 
its initial BART determination at a time when UTac's Line 1 fired only 
natural gas or fuel oil and when UTac's Line 2 fired a variety of fuels 
including coal and petroleum coke. Minnesota determined at that time 
that BART for SO2 for UTac reflected the existing 
particulate matter scrubbers on both lines (without further 
optimization to control SO2 emissions) and fuel blending to 
reduce SO2 emissions on Line 2. Minnesota concluded that 
flue gas desulfurization for these lines was not cost effective.
    UTac subsequently obtained a permit to burn solid fuels on Line 1. 
Best available control technology (BACT) was not required in this 
permit because Minnesota concluded that the fuel blending measures that 
it had determined to be BART for Line 2, which it incorporated into the 
permit, would yield a net SO2 emission reduction. 
Consequently, the fuel change did not constitute a major modification 
requiring BACT. Minnesota also chose not to conduct a revised BART 
analysis, determining limits reflecting existing controls with the 
original fuels and then adopting an

[[Page 8482]]

alternate set of limits that it found equivalent.
    EPA believes that Minnesota improperly rejected the use of flue gas 
desulfurization as a cost effective technology for reducing 
SO2 emissions from UTac's two lines. As discussed in the 
August 15, 2012, notice of proposed rulemaking, EPA believes that flue 
gas scrubbing, particularly in combination with proper fuel blending, 
is considerably more cost effective than the cost effectiveness 
estimates in Minnesota's plan. Furthermore, the significant change in 
operation at the plant warranted reanalysis of BART at this plant. The 
higher sulfur content of the new fuels made more aggressive emission 
control more cost effective, so that a proper reanalysis of BART could 
have concluded that BART for the new configuration reflected more 
control and lower emissions than the original configuration. 
Minnesota's analysis of the plant using its previous fuel mix does not 
adequately evaluate the appropriateness of controls for the plant as it 
is currently operated.\1\
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    \1\ While this rulemaking does not address Federal limits that 
EPA is promulgating elsewhere, it is relevant to note that EPA is 
promulgating final limits based on the source burning low sulfur 
fuels.
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    EPA also has a variety of concerns about the enforceability of 
Minnesota's chosen limits. Minnesota's limits are expressed as 30-day 
rolling averages, but Minnesota in many cases does not require 
continuous emission monitoring systems (CEMS) to provide data for 
evaluating compliance. In the absence of CEMS, Minnesota requires 
``stack testing * * * for 30 hourly data points.'' Even if the average 
of the 30 data points exceeds the emission limit, the data can be 
contested as not necessarily representative of the 720 hours that are 
in a 30-day average. Minnesota has not addressed whether 720 
consecutive hours of stack testing is even practicable, though none of 
the data used to develop emission limits appears to have been collected 
in this manner.
    EPA has special concerns about the enforceability of the CEMS 
requirement for Hibbing Taconite. Minnesota requires that the company 
submit a plan for installing a NOX CEMS, but it is not clear 
from the administrative order thatMinnesota or EPA could take 
enforcement action if Hibbing Taconite failed to install, certify, and 
properly operate a CEMS at this facility.
    The SO2 emission limits in Minnesota's administrative 
orders are expressed in terms of pounds of SO2 emissions per 
long ton of pellets produced. Pellet production is not routinely 
measured at the end of an indurating furnace. Further, the 
administrative orders do not specify methods for determining pellet 
production by indurating furnaces and do not specify any requirement 
for the companies to keep records of pellet production. Therefore, the 
enforceability of these limits is also unclear.
    The administrative order for Hibbing Taconite also provides that 
the company may determine that its limits are not feasible to meet. In 
that case, the order identifies information that the company must 
submit to Minnesota so that the State can consider revised emission 
limits. These provisions raise questions about whether EPA could 
enforce the terms of the administrative order if the company has 
declared the limits to be infeasible.
    EPA also has concerns about the methods for computing emission 
limits. For Arcelor/Mittal and Hibbing Taconite, Minnesota appears to 
have set the limit using the upper predictive limit approach. The 
equation for calculating the upper predictive limit for normally 
distributed data is:
[GRAPHIC] [TIFF OMITTED] TP06FE13.000

Where:

UPL = Upper predictive limit
n = number of data points
m = number of future data points
df = n - 1

X is the mean,
tp,df represents the critical t-value with a p-value of p and df 
degrees of freedom, and
s is the standard deviation

    The available emissions data for these facilities appear not to be 
normally distributed, and so the upper predictive limit equation that 
Minnesota used is not appropriate for this application. In addition, 
the analyses contained in the Minnesota submittal do not appropriately 
apply the upper predictive limit approach for normally distributed 
data. Most notable is the use of inappropriate values for tp,df and m. 
A normal distribution has a lower tail of the distribution with the 
same frequency as the upper tail of the distribution. In seeking, for 
example, to establish the 95th percentile value in a normal 
distribution, a one tailed test must be applied, such that the upper 
tail contains five percent of the distribution and the lower tail is 
simply part of the 95 percent of the distribution at or below the 95th 
percentile value. However, Minnesota selected its values for tp,df 
based on statistics for two tailed tests, which derive, for example, a 
95 percent confidence interval that reflects a 2.5 percent upper tail 
and a 2.5 percent lower tail, which would yield a 97.5th percentile 
value. (Because normal distributions are symmetric, this error can be 
addressed by using a value of tp,df for twice as much frequency outside 
the confidence interval, e.g., using a two-tailed value of tp,df for a 
confidence interval of 90 percent in order to derive the 95th 
percentile value, but Minnesota did not make this adjustment.) Thus, 
Minnesota selected values of tp,df that were unduly high, and higher in 
the emissions distribution than Minnesota was purporting to choose.
    In the above formula, m represents the number of future runs, i.e., 
the number of future data points. Given that the data sets being used 
in the analyses are one-hour averages, with CEMS, the value of m should 
be 720 (30 days times 24 hours). At a minimum, under administrative 
orders that in the absence of CEMS apparently determine compliance on 
the basis of 30 hourly data points (presumably intended to represent 
30-day average emissions), the appropriate value of m would be 30.
    For ArcelorMittal, Minnesota appears to have set the limit based on 
a p-value of 0.01 (which in a normal distribution would yield an upper 
tail of 0.5 percent and thus a 99.5 percentile value) and m = 3. These 
values do not represent appropriate values for p or m.
    Furthermore, Minnesota did not base its limits for this facility 
directly on the original data set, but instead used the 157 original 
data points to create multiple artificial data sets, each including 
2000 sets of 30 values randomly selected from the original 157 values. 
Minnesota then performed statistical analysis of these data sets, using 
the mean of the original 157 data points plus an adjustment based on 
the highest standard deviation among the various artificial data sets 
that was intended to provide a 99th percent upper predictive limit 
value. Minnesota does not justify use of these artificial data sets as 
providing a better representation of emissions or being a better basis 
for determining an appropriate emission limit than direct use of the 
original data set, nor does Minnesota justify using this particular 
combination of statistics.
    Also of note is the fact that the average of the 157 data points is 
significantly higher than the results of stack tests conducted between 
June 2000 and April 2009; specifically, the average is 17 percent 
higher than the highest of these stack test results and 32 percent 
higher than the average of these stack test results. This suggests that 
the data set on which Minnesota used to

[[Page 8483]]

derive its emission limits reflected poorer combustion practice than 
was in place during the prior stack tests. This raises further 
questions as to whether the data sets on which Minnesota bases its 
limits can even be considered to reflect good combustion practice, much 
less BART-level emission control.
    For Hibbing Taconite, Minnesota appears to have set the limit based 
on a p-value of 0.05 (which would represent a 97.5% confidence 
interval) and m = 1. Again, these are not appropriate values for p or 
m.
    For Northshore Mining, Minnesota appears to have had very little 
emissions data available as a basis for setting a limit. The hood 
exhaust portion of the limit appears to be based on one test data point 
multiplied by a ``compliance margin'' of 1.73. The state provided 
inadequate justification for the 1.73 multiplier. The waste gas portion 
of the limit appears to be based on a 95 percent upper confidence limit 
(one-tailed test) and three data points.
    For the U.S. Steel-Minntac and -Keetac facilities, Minnesota set 
facility-wide limits in terms of tons of SO2 per day. 
Minnesota has not demonstrated that limiting the sum of emissions 
across multiple lines requires control and visibility benefits that are 
better than those that would be obtained by requiring BART on each 
line.
    In summary, the BART determinations for taconite facilities in 
Minnesota's plan reflect several deficiencies. Most notably, Minnesota 
inappropriately rejects significant emission control options as being 
infeasible. Minnesota summarily states that low NOX main 
burners are infeasible, without providing the necessary explanation as 
to why this technology could not be applied and without properly 
considering evidence at U.S. Steel's Minntac plant demonstrating 
successful operation of this control. Similarly, Minnesota 
inappropriately rejected control options requiring significant 
reductions in SO2 emissions. Minnesota determined that good 
combustion practice represents BART for NOX control for 
these plants, but the State did not define the measures that constitute 
good combustion practice, the State did not evaluate what good 
combustion practices might be implemented either in general or at 
specific plants, and the State provided no basis to believe that its 
adopted limits in fact reflect good combustion practice. Finally, EPA 
has concerns about the enforceability and the derivation of several of 
the limits in Minnesota's plan.

B. Michigan

    As with Minnesota's plan, EPA's primary concern with Michigan's 
plan for the Tilden Mining facility is the failure of the plan to 
require emission control that fully represents BART. The Michigan plan 
provides no limits on NOX emissions, and Michigan relies on 
a state permit to provide a limit on SO2 emissions that is 
over four times higher than current emissions. Thus, rather than 
require implementation of BART, Michigan's plan allows Tilden Mining to 
increase emissions to levels substantially higher than the levels that 
are occurring now.
    For NOX, Michigan nominally is defining BART to reflect 
``good combustion practices,'' but in fact neither Michigan nor Tilden 
Mining provide any analysis of what these practices might be and 
whether any such measures that are not currently being implemented 
might be required to be instituted. Michigan's plan thus might be 
considered to define BART to reflect existing combustion practices, 
except that Michigan's plan provides no limits that would require even 
the existing combustion practices to be maintained. Instead, Michigan's 
plan states that Michigan ``accepts Tilden's proposal to set a BART 
NOX emission limit in a manner similar to the Minnesota 
Regional Haze SIP. The new NOX limits will be set after 
testing to determine appropriate limits based on `good combustion 
practices' before December 31, 2012.'' See page 36 of the document 
entitled, ``State Implementation Plan Submittal for Regional Haze'' 
dated October 2010. The plan anticipates that the company will perform 
stack testing to develop information on which to base such limits. 
However, Michigan has provided no information to EPA that it has taken 
any of the steps that it would need to take to establish these limits. 
In response to a request under authority of Clean Air Act section 114, 
Tilden Mining provided EPA the results of three stack tests at each of 
the two furnace stacks. However, Michigan has submitted no information 
providing any analysis of emission limits to indicate what limit it 
might find appropriate, and Michigan has evidently not adopted and has 
not submitted any emission limit that would make any definition of 
NOX BART at this facility enforceable.
    Appendix 9H of Michigan's submittal, a document labeled Tilden BART 
Technical Analysis that was apparently prepared by Tilden Mining, 
states that ``[l]ow NOX burners have been installed in the 
preheating section of a straight-grate furnace at another taconite 
plant; however, the [Tilden] indurating furnace does not contain a pre-
heat burner section. If [low NOX burners] were to be applied 
in the indurating zone of the furnace, the reduced flame temperatures 
associated with [low NOX burners] were to be applied in the 
indurating zone of the furnace, the reduced flame temperatures 
associated with [low NOX burners] would adversely affect 
taconite pellet product quality. [Low NOX burners have] not 
been applied to the indurating or preheat zones of any grate-kiln 
taconite furnace. Therefore, this option is not technically feasible.'' 
Michigan's plan accepts Tilden Mining's conclusion that low 
NOX burners are not technically feasible at this facility.
    As noted above, low NOX burners now have been applied to 
a taconite furnace, in particular to the indurating zones of two grate-
kiln furnaces. These applications were found not to have adverse 
effects on product quality. Thus, low NOX burners must be 
considered technically feasible for Tilden Mining's indurating furnace. 
Michigan was aware of the testing of low NOX main burners at 
U.S. Steel's Minntac plant and received comments on the subject before 
the end of the public comment period on its SIP. Insofar as Michigan 
has not conducted an adequate review of the costs, benefits and other 
consequences of implementing this technology, and since this control 
would provide substantially better control compared to current practice 
at the plant and compared to the unlimited NOX emissions 
that Michigan allows, Michigan's plan cannot be considered to require 
BART for NOX at Tilden Mining.
    With respect to SO2, Michigan found several emission 
control options to be feasible, but the State ultimately concurred with 
Tilden Mining's view that none of the options were cost-effective, 
based on costs per ton of SO2 removal ranging from $6,557 
per ton to $22,407 per ton. Michigan rejected use of alternative fuels 
such as natural gas as not required by the BART Guidelines.
    In its August 15, 2012 proposed rulemaking, EPA reviewed the cost 
effectiveness of SO2 emission controls and concluded that 
flue gas desulfurization would be more cost effective than the Michigan 
plan indicated. EPA has received comments on the cost effectiveness of 
this control, and EPA has also received comments from Cliffs Natural 
Resources indicating that limits reflecting the firing of natural gas 
would also be an appropriate basis for setting SO2 emission 
limits for Tilden. EPA will evaluate these comments and any additional 
comments

[[Page 8484]]

that EPA receives in response to today's notice of proposed rulemaking, 
in order to determine whether it considers these findings in Michigan's 
plan to be problematic. In any case, EPA believes that the 
SO2 emission limit for this facility set by Michigan, 
allowing more than four times more emissions than the facility 
currently emits, cannot be considered to represent BART.
    Michigan's plan also states that ``modeling results showed 
SO2 emissions [from Tilden Mining] do not cause visibility 
impairment to the Class I areas.'' However, Michigan's plan does not 
include the information that would be necessary to support a statement 
that is so at odds with the results of other modeling provided in the 
plan. In any case, the furnace and other parts of the facility have 
sufficient impact to be subject to the requirement for BART, and the 
impact of the emissions of one pollutant can be considered as part of a 
five factor analysis of BART but does not justify failing to perform 
the necessary BART analysis, nor can such an analysis justify a 
conclusion that BART reflects substantially greater emissions than the 
facility currently emits.

IV. How does this action relate to the action to promulgate Federal 
requirements for taconite plants?

    As noted above, in an action published August 15, 2012, EPA 
proposed both to promulgate Federal limits representing BART for 
taconite plants in Minnesota and Michigan and to disapprove Minnesota 
and Michigan's plans with respect to BART for these plants. In 
response, EPA received comments objecting that the agency had not 
adequately explained its rationale for proposing to disapprove the 
state submittals. EPA notes that it expressly proposed revisions to 40 
CFR 52.1183 and 52.1235 to disapprove Michigan and Minnesota's plans 
with respect to taconite plant BART and provided extensive discussion 
of the limits needed to satisfy the taconite plant BART requirement, 
which implicitly demonstrated the inadequacy of the states' plans. 
Nonetheless, EPA agrees that further explanation of the basis for its 
proposal to disapprove the state plans is warranted. Therefore, EPA is 
providing this further explanation in this action and is soliciting 
further comments on this topic.
    In these circumstances, EPA views the promulgation of a Federal 
implementation plan (FIP) and the disapproval of the relevant elements 
of the state plans as separable actions. A mandate for promulgating 
Federal limits applies in cases where EPA ``finds that a State has 
failed to make a required submission.'' EPA ``shall promulgate [a FIP] 
within two years'' of such a finding, ``unless the State corrects the 
deficiency, and [EPA] approves the plan or plan revision, before [EPA] 
promulgates such Federal implementation plan.'' See Clean Air Act 
section 110(c)(1)(A). Here, EPA made findings, published on January 14, 
2009, at 74 FR 2392, that Minnesota and Michigan had failed to make 
complete submittals addressing regional haze requirements. Minnesota 
and Michigan subsequently made complete submittals, but because of the 
deficiencies discussed in detail in this notice, EPA has not approved 
these submittals with respect to BART for taconite plants. Therefore, 
the mandate remains for EPA to promulgate a FIP with respect to 
taconite plant BART. EPA notes that the agency's mandate to promulgate 
such a FIP applies without regard to whether EPA has disapproved a 
state submittal. While EPA has proposed to disapprove Michigan and 
Minnesota's regional haze SIPs in this instance, publication of final 
disapproval of the states' submittals is not a prerequisite for 
promulgating a FIP, and EPA must promulgate a FIP in these 
circumstances irrespective of whether it has disapproved the state 
submittals.
    As a result, EPA today is publishing a separate action to 
promulgate a FIP addressing BART for taconite plants in Minnesota and 
Michigan. That action does not address the approvability of the state 
submittals, a subject that will be addressed only after EPA considers 
any additional comments it receives in response to this supplemental 
notice of proposed rulemaking. Conversely, this action only addresses 
the deficiencies in the states' submittals without addressing the 
limits that EPA would find necessary, through Federal promulgation or 
state adoption, to satisfy the BART requirement for these sources. 
Similarly, this action is soliciting further comments on the 
approvability of the state plans with respect to BART for taconite 
plants, but EPA is not soliciting further comments on the FIP that EPA 
proposed to promulgate. In addition, commenters that submitted comments 
on the August 15, 2012, action that addressed the approvability of the 
state submittals need not resubmit those comments; EPA will consider 
those comments as well as any comments it receives in response to 
today's proposal as it prepares final action on the elements of 
Minnesota and Michigan's plans addressing BART for their taconite 
plants.
    In summary, on August 15, 2012, EPA proposed to partially 
disapprove Minnesota and Michigan's plans as failing to satisfy the 
requirements for BART for their taconite plants. Today's supplemental 
notice of proposed rulemaking provides further explanation of EPA's 
rationale for proposing that action and solicits further comment on 
that proposed action.

V. Statutory and Executive Order Reviews.

Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
action is not a ``significant regulatory action'' and, therefore, is 
not subject to review by the Office of Management and Budget.

Paperwork Reduction Act

    This rule does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 
et seq.).

Regulatory Flexibility Act

    This action merely solicits comment on a proposal to disapprove 
state law as not meeting Federal requirements and imposes no additional 
requirements beyond those imposed by state law. Accordingly, the 
Administrator certifies that this rule will not have a significant 
economic impact on a substantial number of small entities under the 
Regulatory Flexibility Act (5 U.S.C. 601 et seq.).

Unfunded Mandates Reform Act

    Because this rule solicits comment on a proposal to disapprove pre-
existing requirements under state law and does not impose any 
additional enforceable duty beyond that required by state law, it does 
not contain any unfunded mandate or significantly or uniquely affect 
small governments, as described in the Unfunded Mandates Reform Act of 
1995 (Pub. L. 104-4).

Executive Order 13132: Federalism

    This action also does not have Federalism implications because it 
does 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 (64 FR 43255, August 
10, 1999). This action merely solicits comment on a proposal to 
disapprove a state plan, and does not alter the relationship or the 
distribution of power and responsibilities established in the Clean Air 
Act.

[[Page 8485]]

Executive Order 13175: Consultation and Coordination With Indian Tribal 
Governments

    Subject to Executive Order 13175 (65 FR 67249, November 9, 2000), 
EPA may not issue a regulation that has tribal implication, that 
imposes substantial direct compliance costs, and that is not required 
by statute, unless the Federal government provides the funds necessary 
to pay the direct compliance costs incurred by tribal governments, or 
EPA consults with tribal officials early in the process of developing 
the proposed regulation and develops a tribal summary impact statement.
    EPA has concluded that this action, in conjunction with the FIP 
promulgation, may have tribal implications. For example, although the 
FIP does not apply to sources in Indian country, controls and emission 
reductions arising from the program may affect Indian country or other 
tribal interests. However, the regulations arising under that action, 
and the SIP disapproval being addressed here, will neither impose 
substantial direct compliance costs on tribal governments, nor preempt 
Tribal law.
    EPA initiated consultation with Tribal officials early in the 
process of developing this regulation to permit them to have meaningful 
and timely input into its development. EPA sent an invitation to 
consult to each Region 5 Tribe on August 15, 2012, along with a copy of 
the proposed taconite FIP Federal Register notice. Conference calls 
were held on the taconite FIP proposal on August 22, 2012 and September 
12, 2012 to provide all Region 5 Tribes with more information on the 
proposed rulemaking and an opportunity to ask questions of EPA 
technical staff and request formal individual consultation if desired. 
Four Region 5 Tribes participated in the August 22, 2012 call. Two 
Region 5 Tribes participated in the September 12, 2012 discussion. One 
Region 5 Tribe provided verbal testimony at the public hearing held on 
the proposed taconite FIP rulemaking on August 29, 2012. One Region 5 
Tribal Chair expressed appreciation for the consultation discussions 
held with the Tribes and gratitude for EPA's careful consideration of 
the regional haze situation in northeast Minnesota.

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

    This rule also is not subject to Executive Order 13045 ``Protection 
of Children from Environmental Health Risks and Safety Risks'' (62 FR 
19885, April 23, 1997), because it solicits comment on a proposal to 
disapprove a state rule.

Executive Order 13211: Actions That Significantly Affect Energy Supply, 
Distribution, or Use

    Because it is not a ``significant regulatory action'' under 
Executive Order 12866 or a ``significant energy action,'' this action 
is also not subject to Executive Order 13211, ``Actions Concerning 
Regulations That Significantly Affect Energy Supply, Distribution, or 
Use'' (66 FR 28355, May 22, 2001).

National Technology Transfer Advancement Act

    In reviewing state submissions, EPA's role is to approve state 
choices, provided that they meet the criteria of the Clean Air Act. In 
this context, in the absence of a prior existing requirement for the 
state to use voluntary consensus standards (VCS), EPA has no authority 
to disapprove a state submission for failure to use VCS. It would thus 
be inconsistent with applicable law for EPA, when it reviews a state 
submission, to use VCS in place of a state submission that otherwise 
satisfies the provisions of the Clean Air Act. Thus, the requirements 
of section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (15 U.S.C. 272 note) do not apply.

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

    Executive Order 12898 (59 FR 7629 (Feb. 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.
    EPA lacks the discretionary authority to address environmental 
justice in this proposed action. In reviewing SIP submissions, EPA's 
role is to approve or disapprove state choices, based on the criteria 
of the Clean Air Act. Accordingly, this action merely proposes to 
disapprove certain state requirements for inclusion into the SIP under 
section 110 and subchapter I, part D of the Clean Air Act and will not 
in-and-of itself create any new requirements. Accordingly, it does not 
provide EPA with the discretionary authority to address, as 
appropriate, disproportionate human health or environmental effects, 
using practicable and legally permissible methods, under Executive 
Order 12898.

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.

    Dated: January 11, 2013.
Susan Hedman,
Regional Administrator, Region 5.
[FR Doc. 2013-01463 Filed 2-5-13; 8:45 am]
BILLING CODE 6560-50-P