May9, 2012

Attn: Compliance T racker, AE -17J Ai1; Enforcement and Compliance Assurance Branch U.S. Enviromnental Protection Agency Reg ion 5 77 W. Jackson Boulevard Ch icago , Illinois 60604

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ruRENFORCEMENTBRANCH U.S. EPA REG!ON 5 

# ArcelorMittal

Re: ArcelorMittal Minorca Mine Inc. Response to Clean Air Act Section 114 Request to Provide Information Regarding Best Available Retrofit Technology (BART) Compliance This letter and the enclosed data disks are the response of ArcelorMittal Minorca Mine Inc. (refened to herein as "Minorca" or "we") to the "Request to Provi de Infonnation Requested Pursuant to Cl ean Air Act" (the "Request"), regarding the iron ore processing facility located at 5950 Old Highway 53 North, which we received on April 12, 20 11. The Request required a response within 15 days of receipt. Upon rec eipt of the request, Minorca asked for and recei ved an extension, making this response due by May 9 1 h. The extension was approved by Molly DeSalle, EPA's contact person for this response. Minorca hereby prov ides this timely r"esponse to the Request, with th e understandings and clarifications noted herein. Minorca has given careful cons id eration to this Request and each of its questions to ensure that its response is accurate and properly tailore d to the infmmation EPA has requested. Most of the information requested i s public infom1ation that has been submitted previously to a regulatory agency, so Minorca is not requesting that any pmiion ofthis response be considered Confidential Business Information. This response restates each of the questions in the Request and provide s a narrative explanation of the responsive infom1ation. Responsive documents are referenced in the nanative and included on the data disks enclosed with this letter. The disks are organized by numbered folders that correspond to the questions below. Each disk is labeled with the company name, folders contained on that disk, and the date of response. Documents responsive to multiple questions are identified in the nanative response to each question, and are included on the disks under the question to which the documents are most responsive. The documents provided have been scanned for viruses using Microsoft Forefront Endpoint Protection software. If you h av e any questions or concerns about the infonnation provided, please direct your questions to Minorca's counsel, Douglas McWilliams , at Douglas.McWilliams@squiresanders.com.U.S. Envirom11ental Protection Agency Attn: Comp liance Tracker, AE-17J May 9, 2012 

# Arce lorMitt a I Page 2

1. Provide process flow diagrams for both the taconite iron ore mmmg and the taconite pellet manufacturing process. Include in th
. e description, at minimum,**b~formation** on the following: mining operations, ore transfer and storage, course ore crushing, fine ore crushing, ore classification screens, ore storage bins, grinding rod/ball mills, separation, thickeners, balling drums/pellet formation, indurating furnace, pellet cooling and storage, and the process boilers. lllclude a detailed narrative process description. and photographs to explain the indurating furnace process. For each photograph, provide a coded diagram/map to clearly identifY the location of the image in thephotograph. Photographs must correspond to each of the process stages described. Responsive documents are included in Folder 01. The folder includes the following 

### ftles:

• Document 1-1 is a facility brochure w hi c h provides an ove rvi ew of the fac ili ty hi story and oper ation overview, including a faci lity process flow diagram and description of each process unit. A more detailed description of the indurating furnace pro cess is provided in th e nanative response below.

• Document 1-2 contains a schematic indurati ng furnac e includi n g an indication of the air flo w direct i o ns and recycling throughout the various zones. This schematic is being provided in li eu of photographs becau se Minorca does not possess cunent photographs of the indurating furnace that would be useful in this context. The schematic is am1otated with letters referenced in the process description below. Minorca's indurating furnace is a straight grate furnace that is capable of producing up to approx imatel y 3.2 million long tons per year (LTPY). It was manufactured by Dravo and startup occm Ted in 1977
. The indurating fum ace contains 8 preheat burners ( 10 MMBtu /hr each), 2 upper burners (60 MMBtulhr each) , and 2 lower bumers (60 MMBtulhr each) . Th e lo wer bumers are not c une ntly in use. The fumace is fueled by natural gas, and i s capabl e of combusting distillate oil as a backup for the upper a nd lower burners. Before the feed enters the furnace, a " heat1h layer " 3 inches deep is laid on the grate b efore "green balls " are placed on top. The hearth layer is m ade ofpre-fired pellets. The heat1h layer protects pallet car s idewalls and grate bars fi·om extreme heat encountered in fir ing and preheat zo nes . The following de scription cmTesponds to lettered sections of the indurating fumace as shown in Document 1-2 ofMinorca's sectio n 114 response. Zone A. First, the green ball s e nter the updraft drying zone . The wann air fi·om the 2nd cooling zone (Zone F) fl ows up fi·o m b elo w the green ball s for initial drying. The h ood exhaust fan draws the warm-moist air from the updraft drying zone and some air from the firing zo n e (Zone D) and send s it to th e scrubbers.

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Zone B
.

Zone C.

Zone D.

Zone E
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Zone F
. Next, the green balls en ter the downdraft drying zone . Hot air from the firing zone supplies the downdraft drying zone. The hot air passes down the pellet bed completing the drying process. The gas is exhausted to the indurator gas scrubber stacks by the windbox exhaust fan. Green balls then enter the preheat zone. Eight (8) preheat burne rs provide the energy input required to calcine fluxstone in the green balls. Hot air from tl). e 1st cooling zone (Zone E) is recycled to the preheat burner down-comers providing combustion and heating air. The windbox exhaust fan discharges gas from the 1st half of the preheat zone to the stacks. The second h alf of the preheat zone is exhausted by the windbox recoup fan. The gas fl:om the windbox recoup fan is used in the downdraft drying zone. Next, the green ball s enter the firing zone. Hot air fiom the 1st cooling zone is recycled to two combustion chambers. The hot air is used for combustion and heating
. Each chamber has a bumer in the roof (the "upper burners") to heat the recycled air b efore it flows down through the bed of green balls
. There are bumers locat ed at the bottom of th e combustion chambers (the " l ower burners") that currentl y are not in u se . Here, the green balls are transform ed from magnetite to hem atite by a process called induration. The green ball s are dried and heated at approximately 18% oxygen and 2450of. The green ball is ref erred to as a pell et after indurati on i s co mpl ete d. A windbox recoup fan collects the hot air and sen ds it to the downdraft drying zone from step B. The fired pellets then go to the 1st cooling zone. The cooling air fans draws ambient air and send s it up throu gh the pellets for cooling . The heated air from the 1 st cooling zone is recycled into the firing zone burner ducts and the preheat burn e r ducts in Zo n e C. The pellets then enter the 2nd cooling zo n e. The cooling air fans draws ambient air and again , sends it up through the pellets for cooling. The he ated air fro m the 2nd cooling zo ne i s recycled t hrough the updraft drying fan into the updraft drying section from Zone A. Jaime Baggenstoss (Enviro mnental Engineer) and Adam Sersha (Process Engi neer) of ArcelorMittal Minorca Mine, with the assistance of Be · au Thurma n of Ban En gineering , provided infonnation for this response. 2. For the time period January 1, 2010 toDecember 31, 2011, provide manufacturing specification and operating data to demonstrate operating parameters for the facility's indurating furnace. Operating parameters and data must include, at a minimum: flue gas composition, entrance

. 3.U.S. Envirom11ental Protection Agency Attn: Compliance Tracker, AE-17J May 9, 2012

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temperature, exit air temperature, preheat zone temperature, burner temperature, pellet residence time, and air flow rate. Two documents summarizing indurating fumace data are included in Folder 02.

• Document 2-1 contains flue gas composition, pellet residence time, and air flow rate data. Flue gas composition and the air flow rate were derived fi:om two recent stack tests conducted in 2011. Pellet residence time was approximated based on the average speed of the fumace belt and length of the furnace between the entrance of the preheat zone and the exit of the firing zone.
• Document 2-2 contains temperature data. Data was collected fiom thennocouples within the furnace and reflect the pre-drying temperature, temperature at the start and end of the pre-heat zone, and temperature at the entrance to the combustion chambers. A diagram of the thermocouple locations is included in this document. Jaime Baggenstoss (Enviromnental Engineer) and Adam Sersha (Process Engineer) of ArcelorMittal Minorca Mine pro v ided infonnation for this response. 3. For the time period January 1, 2007 to December 31, 2011, provide records of the natural gas used by the indurating furnace at the facility
. Document 3-1 is a spreadsheet containing monthly natural gas usage and is included in Folder 03. Natural gas usage information is calculated monthly based on purchase records. Jaime Baggenstoss (Enviromnental Engineer) and Adam Sersha (Process Engineer) of ArcelorMittal Minorca Mine provided infom1ation for this response. 4. For the time period January 1, 2007 to December 31, 2011, if coal was used as a fuel source at the facility, provide documentation of the average sulfur content for coal used by the indurating furnace at the facility. Minorca does not use coal as a fuel source and therefore has no infom1ation responsive to this request. 5. If not already provided to EPA in Mittal's February 16, 2012 Section 114 Information Request Response, provide copies of all stack test conducted on any emissions unit for any reason, and include all test runs, even if a full test series was not completed. Identify the emissions unit, specify the date of the test, test method used, and the filter temperature during the time of the test, if applicable. Provide all calculations relative to the stack test, and provide copies of the full test report, including the section describing the process parameters and production or processing rates at the time of the test, as well as copies of any reports of visible emission

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observations conducted during each test. For each test during which the source was not

· . operating at the maximum design capacity, provide an explanation why production was limited.

As stated in EPA's 114 request, only those stack tests which were not provided in the previous 114 request r ega rding MACT compliance are included in this response . EPA clarified that it was not seeking full test repmts for pmticulate tests, and that Minorca should submit only summary pages identifying the uni t, method , and test results for these tests. Ac cordingl y, only summary pages are included for particulate t ests. Full te st repmts are included for stack tests of other pollutants. M inorca does not operate continuous opacity monitors , and therefore any opacity data collected dming stack testing is included in the stack test reports . Nine stack test repmts are included in Fo lder 05:

• Document 5-T is a 2005 s tack test re port for NOx emissions from the Indurating Fumace. Process operating data during the stack test is provided in Appendix F. This test was not conducted at maximum design capacity because the facility air pennit only requires that production be maintained at greater than 340 LT/hour during testing and the maximum design capacity i s a pproximately 40 0 LT/hour.

• Documents 5

-2a to 5-2g contain s NOx, S0 2 and CO test data from an incomplete study in 2006. A fonnal test repmt was never crea ted, a nd therefore the only d at a avail ab le fio m the se tests is r aw data that was not verified. Available process data i s included in the attached documents.
• Document 5

-3 co ntains the summary pages from a 2006 s t ack te st repmt f or several Taconite M ACT particulate compli ance tests. This te st was no t conducted at maximum design capacity because the f acilit y air p e rmit only requires that production be maintained at greater than 340 LT/ hour dur ing testing and the maximum design capacity i s approximately 400 LT/ hour
. M inorca ha s also included a notic e of compliance letter from MPCA for tlli s stack test (Document 5-3a) , as the itlitial test repmt does not contain an a nal ysis of complim1ce under th e speci al complian ce demonstration pro visions of the Taconite MACT rule. The MPCA letter confirms that Minorca demonstrated comp li ance with the Taconite M ACT emission limits.
• Document 5- 4 i s a 2007 s tack test repor t for the Indurating Furnace for particulate matter, NOx, S0 2 and CO
. Process operating dat a during the stack test is provided in Appendix F
. This test was not conducted at maximum design capacity because the fac ility air penn it o nly requires that production be maintained at greater than 340 LT/hour during testing and the maximum design capa cit y i s approximately 400 LT/hour.
• Document 5-5 i s the 2008 report f or the 7 -d ay stack NOx stack test on the I ndurating Fum ace. Pro cess operating data during the stack te st is provided in Appendi x F. Because this was a

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# ,.~ ArcelorMittal Page 6 multi-day stack test to assess variability under nonnal operating conditions, testing was not perfonned at the maximum production rate.
• Document 5-6 is the 2008 report for the 7-day stack S02 stack test on the Indurating Furnace. Process operating data during the stack te st is provided in Appendix F
. Because this was a multi-day stack test to assess vatiability under nonnal operating conditions, testing was not perfonned at the maximum production rate.
• Document 5-7 is a 2009 report for
. an S02 stack tes t on the Indurat ing Furnace. Process operating data during the stack test is provided in Append ix F. The stack test was conducted to detennine S0 2 emissions dming nonnal operation and therefore was not conducted at the maxi mum production rate.
• Document 5-8 is a 2009 report for a NOx stack test on the Indurating Fumace . Proces s operating data dming the stack test is provided in Appendix F. The stack test was conducted to dete1mine NOx emissions during normal operation and therefore was no t conducted at the maximum emission rate.
• Document 5-9 i s a 2011 report for an S02 stack test on the Indurating Fumace. P rocess operating data dming the stack test is provided in Appendix F
. This test was not conducted at maximum design capacity because the facility air permit only requires th at production be maintained at greater than 34 0 LT/hour during the testing and the maximum design capacity i s approximately 400 LT/hour.
• Documen t 5-10 is a 2011 report for the s t ack NOx stack test on t he Indurating Fumace. Proce ss operating data during th e stack test is provided in Appendix F. This test was not conducted at maximum design capacity b ecause the fa c ilit y air pennit only r equires that producti on be

· maintained at greater than 340 LT/ hour during the te sting and the maximum design capacity is approximately 400 LT/ hour.
• Document 5-11 co nt ai n s the summary pages from a stack test report for several particulate compliance tests. Th ese test s were operating at high production rates (approx imately 90% of the maximum capacity or greater) but may not have been at the maximum design capacit y because raw m aterial quality can imp act the maximum production rates. The facility air pennit o nl y requires that production be maintain ed at greater than 340 LT/hour during testing and th e maximum design capacity is approximately 400 LT/hour. Jaime Baggenstos s (Envirom11ental Engineer) of ArcelorMittal M inorca M ine provided information for this response.

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6. Provide an electronic Excel workbook with the complete nitrogen oxide (NOx) and sulfur dioxide (S0 2) facility-wide potential to emit calculations. Include in the response a written description of how each column in the Excel workbook is generated. Minorca's potential to emit calculations for NOx and S02 are in Document 6 ,. 1 and are included in Folder 06. References are outlined in a separate tab within the spreadsheet and give an explanation of how each calculation was conducted. The potential to emit for the indurating furnace will change when the BART limits for NOx and S02 become effective. For the S0 2 potential to emit, we presumed maximum use ofNo. 2 fuel oil in the firing zone bumers even though this i s not a normal operating condition. PTE calcul ations do not include emissions from insignificant s ource s . Jaime Baggenstoss (Environmental Engineer) of ArcelorMittal Minorca Mine and Erik Boleman of Ban Engineering provided information for this response. · 7. The facility's Best Available Retrofit Technology report, available on the Minnesota Pollution Control Agency Regional Haze website ("BART report"), discusses the low efficiency of the facility's wet scrubber for S0 2 • Provide all documentation, including reports and studies, to determine the current S0 2 efficiency of all water scrubbers at the facility.**Additionally~** provide all documents, including reports and studies, completed for technical feasibility of efficiency upgrades for each scrubber. Several documents regarding wet scrubber S0 2 removal effici ency are included in Folder 07.
• Document 7 -1 is an Evaluation of Mitmesota Taconi te Wet Scrubbers at Minntac, Keetac, HibTac , and UTac by Jolm Engesser (Minnesota Department of Natural Re sources). Page 6 of Engesser's report contains infonnation on scmbber S02 efficiency and page 11 contains desc1iptions of the scmbbers. Minorca's scrubbers are most like Utac ' s Line 2 scrubbers.
• Document 7-2 i s a copy ofMPCA's fonn GI-05A (July 2007). 1. Table GI-05A.l shows a high efficiency we t scrubbers used for particulate control with an S0 2 removal efficiency of 30%
. • Document 7-3 is a memo written by Ban Enginee1ing which explains a statistical anal ysis of S0 2 data from the 7-day stack test conducted in March 2008.

• Document 7-4 i s a memo written in 2007 to exp lain the source of s ulfur from each of Minorca's processes . Minorca does not have any site-specific data to support the control efficiencies indicated in this memorandum, whi ch are based on a convers ation with John Engesser in 2007. Jaime Baggenstoss (Enviromn ental Engineer) of ArcelorMittal Minorca Mine, Erik Boleman of Ban Engineering and Jack Ke1medy of Ban Enginee rin g provided inf om1ation for this respon se.

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. Environmental Protection Age n cy Attn: Compliance Tracker, AE-17J May 9, 2012

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8. The BART report discusses the technical feasibility of low NOx burnet·s and a variety of selective catalytic reduction (SCRs) systems . Pt · ovide all documentation, including reports and studies, to determine the technical feasibility of low NOx burners and SCRs at the facility's indurating furnaces
. Several documents regarding lo w NOx burners and SCRs are included in Folder 08.
• Document 8-1 is an email summary of a phone conversation with representatives of DanieliCorus who had recently completed a major NOx study and low-NOx bumer retrofit at a straight-grate taco nite induration furnace in the Netherlands. Note that at the time o f this email 8/2/2006, this teclmo logy was detem1ined to be "not available " for taconite indurating fumaces because there is only one facility using the technology and the teclmology has not been so ld outs ide of their company.
• Document 8-2 contains an MPCA report prepared by Barr Engineering entitl ed, " Potential Impacts of the Federal Regional Haze and Be st Available Retrofit Teclmology Rules on the Taconite Industry in M innesota" from 2003. Pages 45 , 60, and 65 contain the mo st relevant info 1mation to Low NOx B um ers. Pages 46 and 63 -65 contain the most relevant inf ormatio n to SCR.
• Document 8

-3 i s an inte rn al Barr E n g ineering email indi catin g a 10 % NOx redu ction at a different facility with l ow - NOx bumers**in s~a** **ll ed**  on t h e preheat sect ion
. • Document 8

- 4 co ntain s a proposal and preliminary data from EPS Teclmolo gies, Inc. investigating use of a ca talyst referred to as CFD 24

- 7. A final sununary and analysis was never completed for this st udy because Minorca did not h ave confid ence in the testing or preliminary results produced by EPS Te clmolo gies. To the best ofMinorca's knowledge, this co mpany and product are no l on ger in existence and the proposed technology was not in

ves ti gated fmiher . Jaime Baggenstoss (Environm e ntal E n gineer) of Arc el orMitta l M in orca Mi n e and Erik Bo leman of Barr E ngi n eerin g provided infonnation for this response. 9. The BART report discusses the technical feasibility of overfire air and induced · flue gas technology. Provide all documentation, including reports and studies, to determine the technical feasibility of overfire air and induced flue gas technology at the facility ' s indurating furnace. Infonnation r es p ons ive to this question is included in response t o Questio n 8 in Fo lder 08, Docwnent 8

-2
. Pages 45, 60, and 65 of thi s document con tain the most relevant information to induced flue gas recirculatio n. Th e M inorca BART report o nly addre sses overfire air in Appendi x D wh e r e it is designated as not techni ca ll y feas ib le. The principle behind overfire air is to stage the add it io n of air to limit th e peak flame temperature and excess oxygen in the co mbu sti on zone to limi t t h e fom1ation

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ofNOx. P1imary air is added at the bumer to allow combustion to occur at nearly stoichiom et ric ratios of oxygen. This limits the amount of oxygen which is available to react with nitrogen and fonn NOx. Overfire air is added above the primary flame zone to allow complete combustion to occur in the presence of a small amount of excess oxygen. However, Minorca's indurating fumace does not have a primary combustion zone that can be controlled to near stoichiometric ratios. Oxygen levels in the fumace are in the 15% to 20% range , well above stoichiometric combustion conditions. Therefore overfire air was detennined to be not technically feasible. Erik Bo leman of BatT Engineering and Jack Kennedy of Ban E ngineering, under the direction of Jaime Baggenstoss (Environmenta l Engineer) of Arcelor M ittal Minorca Mine, provided information for this response. 10. Identify the manufacturer, including the contact information, for all low NOx burners, SCR, scrubber, overfire air, and induced flue gas technologies considered technically feasible for use at the facility. The manufacturer company names, contacts, email addresses, and phone numbers are provided below for wet walled electrostatic precipitators (WWESP), secondary scrubbers, and SCR with conventional reheat. Low NOx bumers were also identified as technically feasible in the preheat section of the fumace, h owever these controls are already installed at Minorca and therefore were not considered futiher in the BART analysis. Contro l Manufacturer Contact Contact Emai l Contact Phone Teclmology Name WWESP Dun Rodney Rodeny.P em1ington @durrusa. com 407.822.9203 Pennington Secondary STS Hal Taylor taylor@stsconsultants.com 847.279.2541 Wet Scrubber Consultants SCR Babcock Bob Harold BHarold@babcock2ower.com 508.854.394 1 Power SCR Com1etech Elizabeth GoveyEM@Carmetech. com 9 19. 620
.3000 Govey
Jack Ke1medy of Barr Engineering, under the direction of Jaime Baggenstoss (Enviromnental Engineer) of ArcelorMittal Minorca Mine, provided infonnation for this response. 11. For the time period January 1, 2002, to the date of the receipt of this letter, provide all documentation, including engineering studies or mass balance studies, conducted to determine emissions of NOx from each waste-gas stack at all indurating furnaces at the facility
.

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• Document 11-1 is an internal ArcelorMittal presentation addressing benefits of relocating indurating bumers in the Firing Zone of the fumace.
• Docwnent 11-2 is the ESA Computational Fluid Dynamic Modeling Repmi for predicting NOx emissions from bumer changes.
• Document 11-3 is MPCA's approval letter to ArcelorMittal approving the "altemate method" for monitoring NOx emissions. Jaime Baggenstoss (Enviromnental Engineer) of ArcelorMittal Minorca Mine, Erik Boleman of Barr Engineering and Jack Ke1medy of Barr Engineering provided infom1ation for this response. 12. Provide an electronic Excel workbook listing the following information from the NOx and/or S0 2 continuous emission monitoring system (CEMS) from the date the CEMS were installed to present. Provide the information on an hourly basis, where applicable. The Excel workbook must include the following: a) CEMS indentifying name or marl<:er; b) CEMS location; c) Pollutant monitored; d) Date and time; e) NOx I S02 emissions rate in pounds per million British thermal units (lb/mmBtu); f) Raw NOx I S0 2 in ppm; g) NOx I S0 2 emissions in pounds per hour; b) Flow rate in actual cu. bic feet per minute (ACFM); and i) Furnace temperature in °F. Minorca does not own or operate continuous em1sswns monitors (CEMS) and therefore has no infonnation responsive to this request. 13. Provide written explanation and supporting documents of how the facility could use NOx CEMS for process optimization. Minorca has not conducted an evaluation on how a NOx CEMS could be used for process optimization. Minorca cannot respond to this request without engaging in speculation, and therefore has no infonnation responsive to this question with an adequate foundation for reliability. The section of the BART report which relates to process optimization with a NOx CEMS or other parametric monitoring (page 33) was written in response to MPCA's guidance for BART analyses, which was bas ed on the experience of the electric utility industry. A taconite indurating furnace is different from a utility boiler as it petiains to NOx generation and NOx variability. Minorca's NO x emi s sions are p1imarily a function of thennal NOx and, based on the design o f the furnace and the existing

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equipment, we expect there are few, if any , adjustments that can be made to reduce peak flame temperature to reduce NOx without impacting furnace productivity and quality. Adam Sersha (Process Engineer) of ArcelorMittal Minorca Mine, Erik Boleman of Barr Enginee1ing and Jon Maki of Barr Engineering provided information for this response. 14. For the period January 1, 2002, to the date of the receipt of this letter, provide NOx emissions data from the indurating furnace for each day, and also for a thirty-day rolling average. Data on daily NOx emissions and thirty day rolling averages would require a Continuous Emissions Monitoring System (CEMS). Minorca does not own or operate CEMS and therefore has no infonnation responsive to this request. 15. Identify all NOx emission sources and factors contributing to NOx emissions at the facility's indutating furnace, including but not limited to , the burners. The three mechanisms by which NOx production occurs in an indurating furnace are thennal, fuel, and prompt NOx. Thennal NOx occurs when nitrogen contained in air oxidizes at high temperatures. This occurs primarily in the flame zone of the burners and is a function of high temperature and excess oxygen. The majmity of them1al NOx is fonned during gas combustion, and occurs when high temperatures cause 0 2 to dissociate to 0, which can fonn NO through the following reaction: N 2 

### + 0

= NO 

### + N. Water dissociation or fuel combustion can also produce OH and fonn NO through the following reaction: N 

### + OH = NO 

### + H. Fuel NOx occurs when nitrogen contained in the fuel oxidizes dming combustion. This is most common with coal, oil , and wood combustion, and is also driven by temperature and 0 2 concentration. Prompt NOx makes up a small fi·action of the NOx fmmed during gas combustion
. Prompt NOx occurs at the bume rs as turbulent diffusion mixes fuel and air and creates eddies ideal for NO formation. Erik Boleman of BaiT Engineering, Jack Kennedy of Barr Engineering and Energy Systems Associates provided information for this response. 16. Identify all persons, including employees, consultants, representatives of the taconite industry, or representative of air pollution control manufacturers, who assisted in the preparation, or were consulted for the purpose of preparing, the BART repo i·t. The following personnel at BaiT Engin ee1ing contributed to the BART report:

• Anthony Widboom • Anita Dickson • Andrew Skoglung

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## • Anthony Shoberg 

## • Beth Havlik 

## • Bradley Johnson 

## • Cherie Lemer 

## • Colin J oln1son 

## • Erik Boleman 

## • George Pruclmofski 

## • Joel Trinkle 

## • Jeannette Yanta 

## • J olm Kennedy 

## • Lori Yal ch 

## • Michael Hansel 

## • Marilyn Lindquist 

## • Susan Nel son 

## • Suzanne Johnson 

## • Teresa Kinder 

## • Timothy Russell 

# ArcelorMittal

Erik Boleman, George Pruclmofski, Jo lm Kennedy , and Michael Hansel maintained primary responsibility for the contents of the report. The following manufacturers were consulted for pmpo ses of preparing the BART report:

• Kenneth Gardner (Metso) • Jan Weekes (Outokumpu) • Peter Zmmeveld (Danieli) • Koen Meijer (Danieli) • Bob Schreiber (Schreiber, Y onley, and As sociate s) • Bob Haro ld (Babcock Power) • Elizabeth Govey (Cormtech) • Hal Taylor (STS Consultants) • Rodney Pennington (Durr) The following Minorca employees were consulted for purpo ses of preparing the BART repmi:

• Gus Josephson (retired employee) • Jon Maki (former employee) Jaime Baggenstoss (Enviromnental Engineer) of Ar celorMit tal Minorca Mine and Erik Bol eman of Bar r Engineering provided information for this response.

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-U.S. Environmental Protection Agency Attn: Compliance Tracker, AE-17J May 9, 2012 Page 13 Sincerely,

# ~~(\~ Jonathan Holmes Vice President/Operations Manager

Enclosure

cc: Supervisor, Air Quality Compliance Dete1mination Minnesota Pollution Control Agency 520 Lafayette Road North Saint Paul, Minnesota 55155-4194 Rich Zavoda Jaime Baggenstoss Douglas McWilliams

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