### IN THE UNITED STATES COURT OF APPEALS FOR THE EIGHTH CIRCUIT

CLIFFS NATURAL RESOURCES INC., etal., Petitioners,

v. Case No. 13-1.758 (and consolidated Case Nos. 13-1761, 13-21.26, 13-2129, 13-2130)
U.S.ENVIRONMENTALPROTECTION AGENCY and GINA McCARTHY, ADMINISTRATOR, Respondents.

CLIFFS NATURAL RESOURCES INC., etal., Petitioners,

►v~ U.S.ENVIRONMENTAL PROTECTION AGENCY and GINA McCARTHY, ADMINISTRATOR, Case No. 13- 373 (and consolidated Case Nos. 13-3575, 13-359,14-1710,and 14-1712)

Respondents.

SETTLEMENT AGREEMENT This Settlement Agreement is entered into by Cliffs Natural Resources Inc. ("Cliffs"), ArcelorMittal USA LLC ("ArcelorMittal"), the State of Michigan, and the United States EnvironmentalProtection Agency("EPA")(collectively,the "Parties").

1WHEREAS,Petitioners Cliffs,ArcelorMittal,and the State ofMichigan (collectively the

"Petitioners")each filed a petition for review challenging a final rule promulgated by EPA under sections 110 and 169A ofthe Clean Air Act, 42 U.S.C. §~ 7410 and 7491, entitled "Approval. and Promulgation of Air Qualify Implementation Plans; States of Minnesota and Michigan; Regional Haze State Implementation Plan; Federal Implementation Plan for Regional Haze; Final Rule,"78 Fed.Reg.8,706 (Feb.6,2013)(the "FIP Rule"); WHEREAS,the petitions for review ofthe FIP Rule have been consolidated in this court under lead CaseNo. 13-1758; WHEREAS,Petitioners Cliffs,ArcelorMittal,the State ofMichigan,and U.S. Steel each filed a petition for review challenging a final rule promulgated by EPA under section 110 ofthe Clean Air Act, 42 U.S.C. ~ 741.0, entitled. "Approval and Promulgation of Air Quality Implementation Plans; States ofMichigan and Minnesota; Regional Haze," 78 Fed.. Rea. X9,825 (Sept. 30,2013)(the "SIP Rule"); WHEREAS,the petitions for review ofthe SIP Rule have been consolidated in this court under lead Case No. 13-3573; WHEREAS,Petitioners have raised various challenges to the FIP Rule and the SIP Rule associated with taconite facilities Located in Minnesota and Michigan; WHEREAS,the Parties wish to implement this Settlement Agreement resolving all of Petitioners' challenges to the FIP Rule and the SIP Rule,and thereby avoid protracted and costly litigation and to preservejudicial resources; withoutany admission or adjudication offact or law; NOW,THEREFORE; the Parties, intending to be bound by this Settlement Agreement, hereby agree as follows:

2L No later than five days after this Settlement Agreement is final pursuant to

paragraph 7 of this Settlement Agreement, the Parties shall file joint motions with the court in
Case No. 13-1758 and in Case No. 13-3573 notifying the court ofthis SettlementAgreementand requesting that the Petitioners' claims in each ofthese consolidated cases be held.in abeyance,if the Courthas not already done so. 2. EPA shall send -- as expeditiously as practicable,but not later than ten days after the Settlement Agreement is final (see paragraph 7) -- a letter that grants the petitions for reconsideration.submitted by Cliffs to EPA dated April 3,2013,and November 26,2013,and.by ArcelorMittal on March 22,2013 3. EPA shall. sign -- as expeditiously as practicable but not later than June 12, 2015

-- a notice of proposed rulemaking proposing changes to the FIP Rule that is substantially consistent with,and includes numeric emission limits and time frames identical to those set forth in; Attachment A to this Settlement Agreement. Aspects of the FIP Rule affecting Petitioners
not directly implicated by the terms ofthis Settlement Agreement (including,without limitation, other emissions limits, recordkeeping and other requirements) shall not be altered in EPA's proposed rulemaking. Once signed,the notice ofproposed rulemaking shall be published in the FederalRegister as expeditiously as practicable. 4. The Petitioners shall not file any adverse comments on any portion of the proposed rule under paragraph 3 above ifit is substantially consistent with,and includes numeric emission limits and time frames identical to those set forth in, Attachment A to this Settlement Agreement. This does not preclude Petitioners from commenting on any portion ofthe proposed. rule not expressly addressed in this settlement, including but not limited to the equitable
treatment offacilities not included in this settlement.

### S. If EPA sibs by December 18, 2015, a final rule amending the FIP Rule that

includes changes that are substantially consistent with,and includes numeric emission limits and time frames identical to those set forth in, Attachment ~ to this Settlement Agreement, then. after that final rule has been published in fhe Federal Register, Petitioners and EPA shall promptly file an appropriate pleading for the dismissal ofCase Nos. 13-1758, 13-1761, 13-2126, 13-2129, 13-2130, 13-373,13-575,and 13-3595 with prejudice in accordance ~~ith Rule 42(b) ofthe Federal Rules ofAppellate Procedure,with each party to bear its own costs and attorneys' fees. Further,Petitioners waive any right to challenge in any court or administrative proceeding,
any portion ofthat final rule that is substantially consistent with,and.includes numeric emission. limits and time frames identical to those set forth in,Attachment A to this SettlementAgreement. 6. If EPA does not sitrn by December 18, 2015, a final rule that is substantially consistent with,and includes numeric emission limits and time frames identical to those set forth in, Attachment A to this Settlement Agreement, then Petitioners' sole remedy under this Settlement Agreement with respect to the rules under review in these cases shall be the right to ask the court to lift the stay of proceedings and set Case No. li-178 for oral argument and establish a briefing schedule for CaseNo. 13-3573. 7. The Parties agree and.acknowledge that before this Settlement Agreement.is final,
EPA must provide notice in the Federal Registe~~ and an opportunity for public comment pursuant to section ll3(g) of the Clean Air Act. 42 U.S.C. ~ 7413(8). After this Settlement Agreementhas undergone an opportunity for notice and comment.the EPA Administrator andlor the Attorney General, as appropriate, shall promptly consider any such written comments in determining whether to withdraw or withhold consent to the Settlement Agreement; in

4accordance with section 1li(g)ofthe Clean Air Act. This Settlement Agreement shall become

final. on the date thatEPA provides written notice ofsuch finality to Petitioners.
8. Nothing in the terms ofthis Settlement.Agreement shall be construed.to limit or modify the discretion accorded EPA by the Clean Air Act or by general principles of administrative law. No provision of this Settlement Agreement shall be interpreted as or constitute a commitment or requirement that EPA obligate funds in contravention of the Anti

Deficiency Act, 31 U.S.C. § 1341. Furthermore, nothing in the terms of this Settlement Agreement shall be construed to limit EPA's authority to alter, amend or revise any final rule
EPA may issue pursuantto paragraph 5 or to promulgate superseding regulations or guidance.
9. Nothing in the terms ofthis Settlement Agreement shall be construed to limit or modify the obligations ofCliffs and ArcelorMittal fo obtain permits pursuantfo state and federal law to implementthe provisions ofthis Settlement Agreement. 10. The Parties may extend the dates sef forth in this Settlement Agreement or otherwise modify this Settlement Agreement by a written agreement executed by counsel for the Parties. If a lapse in EPA's appropriations occurs within 120 days prior to the deadline in Paragraphs 3, 5 and 6 of this Settlement Agreement, that deadline shall be extended automatically one day for each day ofdelay caused.by the lapse in appropriations.
11. Each.party shall. bear its own costs, including attorneys' fees, in this litigation. including attorneys' fees and costs associated with monitoring, overseeing, or implementing this Settlement Agreement, and including participation in any administrative proceedings contemplated by this Settlement Agreement. 12. This Settlement Agreement with Attachment A constitutes the complete and. entire a~

Bement among the Parties. All prior conversations, meetings, discussions, drafts and

5writings ofany kind are specifically superseded by this Settlement 1~greement and may not be

used by the Parties to vary or contest the terms ofthis Settlement Agreement or as evidence of the Parties' intent in entering into this SettlementAgreeanent. 13. The undersigned representatives of each party certify that they are fully authorized by the party that they represent to bind that respective party to the ternls of this Agreement.



### D~oLYglas
..McWilliams Squire Pit on Boggs(US)LLP 4900 I~eyower 127Public Square Cleveland,Ohio 44114-1304 T; (216)479-8500 F; (216)479-8780 dou~las.mcwilliams~~squirepb.com Counsel fog Petitzone~ CliffsNaturalResozc~^ces Inc. Allen A.Kacenjar Squire Patton Boggs (US)LLP 4900 Key Tower 127Public Square Cleveland,Ohio 441.14-1304 T: {216)479-8500 F: (216)479-8780 allen.kacenjar cr,squirepb.com Counsel forPetitionerA~celo~Mittal USA LLC

0u°ritings of any kind are speciLicall~~ superseded by this Settlement Agreement and may not be

used by the Parties to vary or• contest the terms ofthis Settlement Agreement or as evidence of the Parties' intent in entering into this Settlement Agreement. 13. "I'he undersigned represEntatives of each party cet•tify that they are frilly authorized by the party that they represent. to bind that respecti~~e party to the terns of this Agreement.



### Douglas A.McWilliams Squire Patton Boggs(US)LLP 4900 Key Tower 1.27 Public Square Cleveland,Ohio 44114-1304 T: (2l6)479-8500 F; (21b)479-87$0 douglas.mcwilliams~squirepb.com Coz~nsel fog Petitioner Cliffs Natural~esoz~rces Inc. r~ Alen A.Kacenjar r~ Squire Patton.Boggs(US)LLP 4900 Key Tower 127Public Square Cleveland,Ohio 441 14-1304 T: (216)479-8500 F: (216)479-8780 a1len.kaceniar(cr~,squirepb.com Counsel foi~Petizione~^A~^celorMzttal USA LLC

### SAM HIRSCH

Acting AssistantAttorney General ,~-~ Environment and Nat.Resources Div. ,~ ~ ~'

Alan D.Greenberg U.S.Department ofJustice 999 18~'Street, Suite 370 Denver,Colorado 80202 T: (303)844-1366 alan.~reenbergnusdoj.~o_v Counsel fo~~Respondent U.S. Envi~~on~nentalProtection Agency and Gina McCaf~thy Dated:December ~~ ,2014 Neil D.Gordon Michigan Dept.ofAttorney General Co-Counsel ofRecord Environment,Natural Resources,and Agriculture Division P.O.Box 30755 Lansing,Michigan 48909 T: (.517)373-7540 ~ordonnl(a,michigan.gov Counsel forPetitione~~ State of Michigan

7ATTACHMENT A

EPA will propose amendments to the following sections of40 C.F.R. Part ~2 that are consistent with the following requirements and include numeric emission limits and time frames identical to those set forth below: Section 52.1183(k}(1) Tilden.
An emission limit of 2.8 lbs NO, ;/MMBtu, based on a 720-hour rolling average, will apply to Tilden Grate Kiln. Line 1 when burning natural gas, and an emission limit of 1.5 lbs NOa/MMBtu,based on a 720-hour rolling average,will apply to Tilden Grate Kiln Line 1 when burning a mixture of coal and natural gas. These emission limits will become enforceable 60 months after the effective date ofthis rule and only after EPA's confirmation or modification of the emission limit in accordance with the procedures set forth below. Compliance with these emission limits will be demonstrated with.data collected by a continuous emissions monitoring system (GEMS)for NOS. The owner or operator must collect GEMS data for NO, ; and SO? and submit the data to EPA no later than 30 days from the end ofeach calendar quarter after the effective date ofthe rule until ~7months from the effective date ofthe rule.
No later than.48 months after the effective date ofthe rule,the owner or operator must submit to EPA a report, including any final reports)completed by the selected NOa reduction technology supplier and furnace retrofit engineer,containing a detailed engineering analysis and modeling of the NO,reduction control technology being installed on Tilden Grate Kiln Line 1. The NOX reduction control technology must be designed to meet emission limits of 2.8 lbs NOS/MMBtu when burning natural gas and 1.5 lbs NOx/MMBtu when. burning mixed fuels (e.g., coal and natural gas). This report must include a list ofall variables that can reasonably be expected to have an impact on NOa emission control technology performance, as well as a description of how these variables can be adjusted to reduce NOx emissions to meet the NO, ; design emission limit. The NOS reduction control technology shall. be installed. on Tilden Grate Kiln Line 1 furnace no later than ~0 months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation ofthe NOX reduction control technology or (ii) 50 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 until 57 months from the effective date of the rule. The pellet quality analyses shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv) after tumble, and {v) 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



### D

### 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 ofthe analysis and,in order to define the time period when pellets were produced outside ofthe defined acceptable range for the pellet quality factors listed,provide copies ofthe production logs that document the starting and ending times for such periods. The owner or operator shall provide an explanation ofcauses for pellet samples that fail to meetthe acceptable range for any pelletquality analysis factor. Pellet quality information and data may be submitted to EPA as Confidential Business Information.
No later than 57 months after the effective date ofthe rule,the owner or operator may submit to EPA a report to either confirm or modify the NOa limits for Tilden Grate Kiln Line 1 within the upper and lower bounds described below. EPA will review the report and either confirni or modify the NOa limits. Ifthe 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 provided at the end ofthis attachment. Ifthe CEMS data collected during operating periods between months 50 and ~7 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 at the end ofthis attachment. 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 listed. above 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 dime 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 NOa reduction control technology that were installed. EPA will take final agency action by publishing its final confirmation or modification ofthe NOa limits in the Federal Register no later than 60 months after the effective date ofthe rule. The confirmed or modified NOa limit for Tilden Grate Kiln Line 1 when burning only natural gas may be no lower than. 2.8 lbs NOt/MMBtu,based on a 720-hour rolling average, and may not exceed 3.0 lbs NOX /MMBtu, based on a 720-hour rolling average. T11e confirmed or modified NOa limit for Tilden Grate Kiln Line 1 when.burning mixed fuel 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. If the owner or operator submits a report proposing a single NOa 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 60months from the effective date ofthis rule. Section ~2.1.183(k)(3)



### 0

### The owner or operator ofthe Tilden Grate Kiln Line 1 furnace shall meet an emission limit of

500 lbs SOZ/hr based on a 30-day rolling average beginning 6 months after the effective date of the rule. The Tilden Grate Kiln Line 1 furnace shall not be limited to natural gas fuel. Beginning 6 months after the effective date ofthe 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 SOZ limit.based on twelve continuous months ofCEMS emissions data and submit such limit, calculations, and CEMS data.to EPA no later than 36 months after the effective date ofthe rule. If the submitted CEMS SO? hourly data is normally distributed, the SOZ 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. Ifthe submitted CEMS S02 hourly data is not normally distributed, the SOS lbs/hr emission rate shall be based on the non-parametric equation provided atthe end ofthis attachment. Compliance to the SOZ 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 ofthe SOS limit in the Fede~~al Register• no later than 39 months after the effective date of the rule. EPA. may adjust the 500 lbs/hr SOZ limit downwaxd to reflect the calculated SOz emission rate; however,EPA will not increase the SO, limit above SOO lbs/hr.

Section 52.1235(b)(1)(ii) Hibbing Line 1.
An emission limit of 1.2 lbs NO, ;/MMBtu, based on a 30-day rollins average, will apply to Hibbing Line 1 when burning natural gas. This emission limit will become enforceable 37 months after the effective date ofthis rule and only after EPA's confirmation or modification of the emission limit in accordance with the procedures set. forth below. Compliance with these emission limits will be demonstrated with dafa collected by a continuous emissions monitoring system (GEMS)for NOx. The owner or operator ofHibbing Line 1 must install a GEMS for NOx and SO? within 6months from the effective date ofthe rule. The owner or operator must collect GEMS data and submit the data to EPA no later than 30 days from the end ofeach calendar quarter after that installation. deadline until 34 months from the effective date ofthe rule.
No later than 24 months after the effective date ofthe rule the owner or operator must submit to EPA a report,including any final reports)completed by the selected NOx reduction technology supplier and furnace retrofitengineer,containing a detailed engineering analysis and modeling of the NOh reduction control technology being installed on Hibbing Line 1. Tile NO, ; reduction control technology must be designed to meet an emission limit of 1.2 lbs NOX/MMBtu. This report must include a list ofall process and control technology variables that can.reasonably be expected to have an impact on NOa emissions control technology performance, as well as a description of how these variables can. be adjusted to reduce NO, ; emissions to meet the NOx

10design emission limit. The NOx reduction control technology shall be installed on Hibbing Line

1 furnace no later than 26 months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation ofthe 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. ofeach calendar quarter until 34 months from the effective date of the rule. The pellet quality analyses shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv) after tumble, {v) low temperature disintegration, and (vi) 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 Ribbing's ISO 9001 quality management system. The owner or operator shall provide pellet quality analysis testing results that state the date and time ofthe 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.ofcauses 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.
No later than 34 months after the effective date ofthe 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. Ifthe 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 provided at the end ofthis attachment. Ifthe CEMS data collected during operating periods between months 26 and ~4 that both meet pellet quality specifications and. proper furnace/burner operation are not nornlally distributed, the limit adjustment determination shall be based on the non-parametric equation provided.at the end ofthis attachment. The data set for the determination shall exclude periods when pellet quality did not fall within the defined acceptable ranges ofthe pellet quality factors listed. above and for any subsequent period when production has been reduced in response to pellet quality concerns consistent with Ribbing's ISO 9001 operating standards. Any excluded.period will commence at the time documented on the production log demonstrating pellet.quality did not fall within the defined.acceptable range and. shall end when pellet quality within the defined acceptable range has been. re-established. at planned.production levels,which.will be presumed to be the level that existed immediately prior to the reduction in production due to pellet quality concerns. EPA may also exclude data where operations are inconsistent wiih the reported desib parameters of the NOx reduction control technology installed. EPA will take final agency action by publishing its final confirmation. or modification ofthe NOx limit in the FederalRegister no later than 37 months after the effective date ofthe rule, The confirmed or modified NOa limit for Hibbing Line 1 when burning only natural gas may be

11no lower than 1.2 lbsNOx/MMBtu,based on a 30-day rolling average,and may not exceed 1.8

lbsNOX/MMBtu,based on a 30-day rolling average.

Hibbing Line 2.
An emission limit of 1.2 lbs NOX/MMBtu, based on a 30-day rolling average, will apply to Hibbing Line 2 when burning natural gas. This emission limit will become enforceable 55 months after the effective date ofthis rule and only after EPA's confirmation.or modification of the emission limit in accordance with the procedures set forth below. Compliance with these emission limits will be demonstrated with data collected by a continuous emissions monitoring system (GEMS)for NOa. The owner or operator ofHibbing Line 2must install a GEMS for NOx and SOZ within 6months from the effective date ofthe rule. The owner or operator must collect GEMS data and submit the data to EPA no later than 30 days from.the end ofeach calendax quarter after that installation date until 52months from the effective date ofthe rule.
No later than 42 months after the effective date ofthe rule the owner or operator must submit to EPA a report, including any final reports)completed by the selected NOx reduction technology supplier and.furnace retrofit engineer.containing a detailed engineering analysis and modeling of the NOa reduction control technology being installed on Hibbing Line 2. Tile NOk reduction control technology mush be designed to meet an emission limit of 1.2 lbs NOX/MMBtu. This report must include a list ofall 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 NOt emissions to meet the NOx design emission limit. The NOx reduction control technology sha11 be installed on Hibbing Line 2furnace no later than 44months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation. ofthe NOx reduction control technology; or (ii) 44 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 ofeach calendar quarter until 52 months from the effective date of the rule. The pellet quality analyses shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv) after tumble, (v) low temperature disintegration, and (vi) 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 Ribbing's ISO 9001 quality managen7ent system. The owner or operator shall provide pellet quality analysis testing results that state the date and time ofthe 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 ox operator sha11 provide an explanation ofcauses for pellet samples that fail

12to meet the acceptable range for any pellet quality analysis factor. Pellet quality information and

data may be submitted to EPA as Confidential Business Information.
No later than 52 months after the effective date ofthe rule,the owner or operator may submit to EPA a report to either confirm or modify the NOx limits for Hibbing Line 2furnace within the upper and. lower bounds described below. EPA will review the report and either confirm or modify the NOx limits. Ifthe 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 provided at the end ofthis attachment. Ifthe CEMS data collected during operating periods between months 44 and 52 that both meet pellet qualify specifications and proper furnace/burner operation are not normally distributed, the limit adjustment determination shall be based on the non-parametric equation provided at the end ofthis attachment. The data set for the determination shall exclude periods when pellet quality did not fall within the defined acceptable ranges ofthe pellet quality factors listed above and for any subsequent period when production has been reduced in response to pellet quality concerns consistent.with Hrbbing's ISO 9001 operating standards. Any excluded.period will commence at the time documented on the production log demonstrating pellet quality did not fall within the defined acceptable range and shall end when pellet quality within the defined acceptable range has been re-established at planned production levels, which will be presumed to be the level that existed immediately prior to the reduction in production due to pellet quality concerns. EPA may also exclude data where operations are inconsistent with the reported design parameters of the NOx reduction control technology installed. EPA will take final. agency action by publishing its final confirmation or modification ofthe NOx limit in tlse FederalKegister no later than 5~ months after the effective date ofthe rule, The confirmed or modified NOS limit for Hibbing Line 2when burning only natural gas may be no lower than 121bsNOa/MMBtu,based on a 30-day rolling average,and may not exceed 1.8 lbsNO,~/MMBtu,based on a 30-day rolling average.
Hibbing Line 3.
An emission limit of 1.2 lbs NO,/MMBtu, based on a 30-day rolling average, will apply to Hibbing Line 3 when burning natural gas. This emission limit ~~ill become enforceable 60 months after the effective date ofthis rule and only after EPA's confirmation or modification of the emission limit in accordance with the procedures set forth below. Compliance with these emission limits wi11 be demonstrated with data collected by a continuous emissions monitoring system (CEMS)

for NOS. The owner or operator ofHibbing Line 3 must install a CEMS for NOx and SOS within 6 months from the effective date ofthe rule. The owner or operator must collect CEMS data and submit the data to EPA no later than 30 days from the end ofeach calendar quarter after that installation date until 57months from the effective date ofthe rule.

13No later than 48 months after the effective date ofthe rule the owner or operator must submit to

EPA a report, including any final reports)completed by the selected NOx reduction technology supplier and furnace retrofit engineer,containing adetailed engineering analysis and modeling of the NOX reduction control technology being installed on Hibbing Line 3. The NOh reduction control technology must be designed to meet an emission 1imi~ of 1.2 lbs NOa/MMBtu. This report must include a list ofall 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. The NOx reduction control technology shall be installed on Hibbing Line 3furnace no later than 50 months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation ofthe NOx reduction control technology; or (ii) 50 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 sha11 provide the results from pellet quality analyses no later than. 30 days from the end ofeach calendar quarter until ~7 months from the effective date of the rule. The pellet quality analyses shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv) after tumble, (v) low temperature disintegration, and (vi) 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 Ribbing's ISO 9001 quality management system. The owner or operator shall provide pellet quality analysis testing results that state the date and time ofthe 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 ofcauses for pellet samples that fail to meek the acceptable range for any pellet quality analysis factor. Pellet quality information and data may be submitted to EPA as Confidential Business Information.
No later than 57 months after the effective date ofthe rule,the owner or operator may submit to EPA a report to either confirm or modify the NOx limits far Hibbing Line 3 fun7ace within the upper and. lower bounds described below. EPA will review the report and either confirnl or modify the NOx limits. Ifthe 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 provided at the end ofthis attachment. Ifthe CEMS data collected.during operating periods between months 50 and 57 that. both meet pellet quality specifications and proper fiunace/burner operation are not normally distributed,the limit adjustment determination shall be based on the non-parametric equation provided at the end ofthis attachment. The data set for the determination shall exclude periods when pellet quality did not fall within the defined acceptable ranges ofthe pellet quality factors listed above and for any subsequent period when production.has been reduced in response to pellet quality concerns consistentwith Ribbing'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

14planned 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. EPA will take final agency action by publishing its final confirmation or modification ofthe NOx limit in the Fede~~alRegister° no later than 60 months after the effective date ofthe rule, The confirmed or modified NOa limit for Hibbing Line 3 when burning only natural gas may be no lower than 1.2 lbs NOa /MMBtu,based on a 30-day rolling average,and may not exceed 1.8 1bsNO,/MMBtu,based on a 30-day rolling average.

Section 52.1235(b)(1)(i~c~)
UTAC Line 2.
An emission. limit. of 2.8 lbs NO, ;/MMBtu,based on a 720-hour rolling average, will apply to UTAC 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,will apply to UTAC Grate Kiln Line 2 when bunging a mixture of coal and natural gas. These emission limits will become enforceable 55 months after the effective date ofthis rule and only after EPA's confirmation or modification of the emission. limit in accordance with the procedures set forth below. Compliance with these emission limits will be demonstrated with data collected by a continuous emissions monitoring system (GEMS)for NOk
. The owner or operator must collect GEMS data for NOa and SOS and submit the data to EPA no later than 30 days from the end.ofeach calendar quarter after the effective date ofthe rule until 52months from the effective date ofthe rule.
No later than 42 months after the effective date ofthe rule,the owner or operator must submitto EPA a report, including any final reports)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 UTAC Grate Kiln Line 2. The NOS 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 mixed fuels (e.g., coal and natural gas). This report must include a list ofall variables that can reasonably be expected to have an impact on NOk emission control technology performance, as well as a description of how these variables can be adjusted to reduce NOa emissions to meet the NOY design emission. limit. The NOX reduction control technology shall be installed on UTAC Grate Kiln Line 2 furnace no later than 44 months after the effective date ofthe rule. Corrunencing on the earlier of(i) six months from.the installation ofthe NOa reduction control technology or (ii) 44 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 ofeach.calendar quarter

15until 52 months from the effective date of the rule. The pellet quality analyseis shall include

results for the following factors: (i)compression,(ii)reducibility, (iii) before tumble,(iv) after tumble, and (v)low temperature disintegration. For each ofthe 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 UTAC's ISO 9001 quality management system. The owner or operator shall provide pellet quality analysis testing results that state the date and time ofthe analysis and,in order to define the time period when pellets were produced outside ofthe defined acceptable range for the pellet quality factors listed, provide copies ofthe production logs that document the starting and ending times for such periods. The owner or operator shall provide an explanation ofcauses for pellet samples that fail to meet.the acceptable range for any pellet quality analysis factor. Pellet quality information and data.n ay be submitted to EPA as Confidential Business Information.
No later than 52 months after the effective date ofthe rule,the owner or operator may submit to EPA a report to either confirm or modify the NOX limits for UTAC Grate Kiln Line 2 within the upper and lower bounds described below. EPA will review the report and either confirm. or modify the NOa limits. Ifthe 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 t11e appropriate (depending upon whether data. are statistically independent or dependent) 95% upper predictive limit (UPL)equations provided atthe end ofthis attachment. Ifthe 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 at the end ofthis attachment. The data set for the determination.shall exclude periods when pellet quality did not fall within the defined acceptable ranges ofthe pellet quality factors listed above and for any subsequent period when production had been reduced in response to pellet quality concerns consistent with UTAC'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 tihe 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. EPA will take final abency action by publishing its final confirmation or modification ofthe NOX limits in the FedeYal Register no later than 55 months after the effective date ofthe rule. The confirmed or modified NOa limit for UTAC Grate Kiln Line 2 when burning only natural gas may be no lower than 2.8 lbs NOa/1VIMBtu, based on a 720-hour rolling average, and may not exceed. 3.0 lbs NOa/MMBtu, based. on a 720-hour rolling average. The confirmed or modified NOa limit for UTAC Grate Kiln Line 2when burning mixed fuel may be no lower than L~ lbs NO,

;/MMBtu, based on a 720-hour rolling average, and may not exceed 2.5 lbs NOX /NIMBtu, based on a 720-hour rolling average. If the owner or operator submits a report proposing a single NOa limit for all fuels,EPA may approve the proposed NOX limit for all fuels

16based on a 30-day rolling average. The confirmed or modified limit will be established and

enforceable within 55 months from the effective date ofthis rule.

UTAC Line 1.
An emission limit of 2.8 lbs NOX /MMBtu,based on a 720-hour rolling average, will apply to UTAC 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,will apply fo UTAC Grate Kiln Line 1 when burning a mixture of coal and natural gas. These emission limits will become enforceable 37 months after the effective date ofphis rule and only after EPA's confirmation or modification of the emission limit in accordance with the procedures set forth. below. Compliance with these emission limits will be demonstrated with data collected by a continuous emissions monitoring system (GEMS)for NOx. The owner or operator must collect GEMS data for NO, ; and SOS and submit the data to EPA no later than 30 days from the end ofeach calendar quarter after the effective date ofthe rule until 34months from the effective date ofthe rule.
No later than 24 months after the effective date ofthe rule,the owner or operator must submit to EPA a report, including any final reports)completed by the selected NOX reduction technology supplier and.furnace retrofit engineer,containing a detailed engineering analysis and modeling of the NO,, reduction confrol technology being installed on UTAC Grate Kiln Line 1. The NOX reduction.control technology must be designed to meet emission limits of 2.8 lbs NOX/MMBtu when burning natural. gas and l.~ lbs NOX/MMBtu when burning mixed fuels (e.g., coal and natural gas). This report must include a list ofall variables that can reasonably be expected to have an impact on NOh emission. control technology performance, as well as a description of how these variables can be adjusted to reduce NOS emissions to meet the NOX design. emission limit. The NOX reduction control technology shall be installed on UTAC Grate Kiln Line 1 furnace no later than 26 months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation ofthe 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 analysis. The owner or operator shall provide the results from pellet quality analysis no later than 30 days from the end of each calendar quarter until 34 months from the effective date of the rule. The pellet quality analysis shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv)after tumble, and (v)low temperature disintegration. For each of the pellet qualit~~ 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 customer's pellet specifications that are contained in UTAC's ISO 9001. quality management system. The owner or operator shall provide pellet quality analysis testing results that state the date and time ofthe analysis and,in order to define the time period when pellets were produced outside ofthe defined acceptable range for the pellet quality factors listed,provide copies ofthe production logs that document the starting and ending times for such periods. The owner or operator shall provide an explanation ofcauses for pellet samples that fail to meet the acceptable

17range for any pellet quality analysis factor. Pellet quality information and data may be submitted

to EPA as Confidential Business Infornlation.
No later than 34 months after the effective date ofthe rule,the owner or operator may submit to EPA a report to either confirm or modify the NOX limits for UTAC Grate Kiln Line 1 within the upper and. lower bounds described below. EPA will review the report and. either confirm or modify the NOS limits. Ifthe CEMS data collected during operating periods between months 26 and 34 that. both meet pellet quality specifications and proper furnace burner operation is nornlally 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 provided at the end ofthis attachment. Ifthe 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.at the end ofthis attachment. The data set for the determination shall exclude periods when pellet quality did not fall within.the defined acceptable ranges ofthe pellet quality factors listed above and for any subsequent period when production had been reduced in response to pellet quality concerns consistent with UTAC'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. EPA will take final agency action. by publishing its final confirmation or modification of the NUk limits in the h'ederal Kegister no later than 37 months after the effective date ofthe rule. The confirmed or modified NOa limit for UTAC Grate Kiln Line 1 when burning only natural gas may be no lower than 2.8 lbs NOa /MMBtu,based on a 720-hour rolling average, and may not exceed 3.0 lbs NOh/MMBtu, based on a 720-hour rolling average. The confirmed or modified NOa limit for UTAC Grate Kiln Line 1 when burning mixed fuel may be no lower than l.~ lbs NOx/MMBtu, based on a 720-hour rolling average, and may not exceed 2.5 ibs NO, ;/MMBtu, based on a 720-hour rolling average. If the owner or operator submits a report. proposing a single NO,; limit for all fuels,EPA may approve the proposed NOa limit for all. fuels based on a 30-day rolling average. The confirmed or modified limit will be established and enforceable within 37months from the effective date ofthis rule.
52.1235(b)(2)(iv):
An aggregate emission limit of529.0 ibs SO~/hr,based on a 30-day rolling average, shall apply to the Line 1 pellet furnace (EU040)and Line 2pellet furnace (EU042)beginning 6months after the effective date ofthe rule. Beginning b 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 fordetermining the sulfur content ofcoal must be described in the monitoring plan required for this

furnace.

Section 52.1235(b)(1)(v) ArcelorMittal.
An emission limit of 1.2 lbs NOX/MMBtu,based on a ~0-day rolling average, will apply to the indurating furnace when burning natural gas. This emission limit will become enforceable 55 months after the effective date ofthis rule and only after EPA's confirmation or modification of the emission limit in accordance with the procedures set forth below. Compliance with these emission. limits will be demonstrated with data collected. by a continuous emissions monitoring system (GEMS)for NO, ;. The owner or operator of the ArcelorlVlittal Minorca Mine indurating furnace must install. a GEMS for NOx and SOZ within 6 months from the effective date of the rule. The owner or operator must collect GEMS data and submit the data.to EPA no later than 30 days from the end ofeach calendar quarter after that installation deadline until 52 months from.the effective date of the rule.
No later than 42 months after the effective date ofthe rule the owner or operator must submit to EPA a report, including any final reports)completed.by the selected NOx reduction technology supplier and furnace retrofit engineer,containing a detailed engineering analysis and modeling of the NOa reduction control technology being installed on the ArcelorMittal Minorca Mine indurating furnace. The NOa reduction control technology must be designed to meetan emission limit of 12 Ibs NOt

/MMBtu vvhen burning natural gas. This report must include a list of all process and control. technology variables that can reasonably be expected to have an impact on NOa emissions control technology performance, as we11 as a description ofhow these variables can be adjusted to reduce NOa emissions to meet the NOX design emission limit. The NOx reduction. control technology shall be installed on the ArcelorMittal Minorca Mine indurating furnace no later than 44 months after the effective date ofthe rule. Commencing on the earlier of(i) six months from the installation ofthe NOx reduction contral technology; or (ii) 44 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 ofeach calendar quarter until. 52 months from the effective date of the rule. The pellet quality analyses shall include results for the following factors: (i) compression,(ii) reducibility, (iii) before tumble,(iv) after tumble,(v) low temperature disintegration, and (v) 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 ofthe analysis and, in order to define the time period when pellets were produced outside ofthe defined acceptable range for the pellet quality factors listed,

19provide copies ofproduction or scale data that documents the starting and ending times for such

periods. The owner or operator shall provide an explanation ofcauses 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.
No later than 52 months after the effective date ofthe 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. Ifthe 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 provided at the end ofthis attachment. Ifthe 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 at the end. ofthis attachment. The data set for the determination shall exclude periods when pellet quality did not fall within the defined acceptable ranges ofthe pellet quality factors listed above 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 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. EPA will take final agency action by publishing its final. confirmation or modification ofthe NOx limit in the FederalRegister no later than ~5 months after the effective date ofthe rule, The confirmed or modified NOh limit for the ArcelorMittal Minorca Mine indurating furnace when. burning only natural gas may be no lower than 1.2 lbs NOh/MMBtu,based on a 30-day rolling average,and may not exceed 1.8 lbsNOX/MMBtu,based on a 30-day rolling average.

SI]Equations:

Equation for Normal Distribution and Statistically IndependentData

-r, '~: ax Where:
:~ =average or mean oftestrun data;

~~,~,~_~,~,~~~~-,,~ = t score,the one-tailed t value ofthe Student's t distribution for a specific degree offreedom (n-1)and a confidence level (0.95;0.99 for Tilden SOS)
s~ =variance ofthe dataset;
a~ =number ofvalues t =number ofvalues used to calculate the test average (m = 720 as per averaging time)

To determine ifstatistically independent,use the Rank von.Neumann Test on p. 1~7 ofdata Quality Assessment: Statistical Methods for Practitioners EPA QA/G-9S. Alternative to Rank von Neumann.test to determine ifdata are dependent,data are dependent if t test value is greater than t critical value,where:

i L~P~3

rL - 1

_~~ ~i p =correlation between data points ~r~.tie~~ = t~~3

~_~~a~~y ~~~~ = t score,the two-tailed t value ofthe Student's t distribution for a specific degree offreedom (n-2)and a confidence level (0.95)

Ifdata are dependentthen use the following equation. Equation for NormalDistribution and Data not Statistically Independent { ~ ,. ~ i
Where: p =correlation.between data points

21Non-parametric Equations for Data NotNormally Dis~ribnted

rn =~n ~ ~~ x a
r~ =the rank ofthe ordered.data point,when data is sorted smallest to largest
n =number ofdata points
c~ =0.95,to reflect the 95~'percentile Ifm is a whole number,then the limit,UPL,shall be computed.as:

Where:

~,,~ =value ofthe mth datapoint in terms oflbs SO,/hr or lbsNOX/MMBtu,when the data is sorted smallest to largest. Ifm is not a whole number,the limit shall be computed.by linear interpolation according to the following equation.

where

~r~; =the integer portion ofrn,i.e.,m truncated at zero decimal.places; and
are =thedecimal portion ofm

22