Cleveland Cliffs Incorporated: Northshore MiningBART Report - Appendix A Emission Control Cost AnalysisTable 1: Cost SummaryNOxControl Cost SummaryControl TechnologyControlEff %ControlledEmissions T/yEmissionReduction T/yrInstalled CapitalCost $Total Annual Cost$/yrPollution ControlCost $/tonFurnace 11 Hood Exhaust80%5.7 106.7 $46,019,283 $11,628,024 $108,969Furnace 11 Waste Gas80%17.8 255.9 $43,197,692 $8,239,261 $32,199Furnace 12 Hood Exhaust80%5.6 104.4 $46,284,809 $11,688,411 $112,008Furnace 12 Waste Gas80%17.4 250.3 $43,455,895 $10,383,373 $41,488SO2Control Cost SummaryControl TechnologyControlEff %ControlledEmissions T/yEmissionReduction T/yrInstalled CapitalCost $Total Annual Cost$/yrPollution ControlCost $/tonWet Walled Electrostatic Precipitator (WWESP)Furnace 11 Hood Exhaust80% 5.7 22.9 $23,617,556 $4,188,875 $182,993Furnace 11 Waste Gas80% 1.9 7.6 $21,846,389 $3,799,211 $496,949Furnace 12 Hood Exhaust80% 5.3 21.0 $23,617,556 $4,294,171 $204,058Furnace 12 Waste Gas80% 1.8 7.0 $21,846,389 $3,764,113 $535,575Wet ScrubberFurnace 11 Hood Exhaust60% 11.4 17.2 $16,952,864 $2,401,349 $139,872Furnace 11 Waste Gas60% 3.8 5.7 $15,859,420 $2,201,975 $384,034Furnace 12 Hood Exhaust60% 10.5 15.8 $16,952,864 $2,401,349 $152,149Furnace 12 Waste Gas60% 3.5 5.3 $15,859,420 $2,201,975 $417,742Selective Catalytic Reduction with ReheatY:\23\00 MN Taconite BART (2006)\Facility BART Reports\NMC\NMC Furnace-Process Boiler\Appendices\Appendix A - NMC Control Costs.xlsCost Summary9/6/2006 Page 1 of 56Cleveland Cliffs Incorporated: Northshore MiningBART Report - Appendix A Emission Control Cost AnalysisTable 2: - Summary of Utility, Chemical and SupplyCostsOperating Unit:Furnace 11 Hood ExhaustStudy Year2006Emission Unit Number EU 100Stack/Vent Number SV 101, 102, & 103Operating Unit:Furnace 11 Waste GasEmission Unit Number EU 104Stack/Vent Number SV 104 & 105Operating Unit:Furnace 12 Hood ExhaustEmission Unit Number EU 110Stack/Vent Number SV 111, 112, & 113Operating Unit:Furnace 12 Waste GasEmission Unit Number EU 114Stack/Vent Number SV 114 & 115ReferenceItem Unit Cost Units Cost Year Data Source NotesOperating Labor50 $/hr2006Site Specific - Northshore Mining .Maintenance Labor60 $/hr2006Site Specific - Northshore Mining .Construction Labor Rate.Electricity0.060 $/kwh2006Site Specific - Northshore Mining.Purchased.Natural Gas10.0204 $/mscf2006Site Specific - Northshore Mining . $9.40/MMBtu @ 1066 Btu/scf.Water0.28 $/mgal 0.20 1995EPA Air Pollution Control Cost Manual, 6thEd 2002, Section 5 Ch 1, page 1-40.Annual Costs for Packed Tower Absorber Example Problem. '95 costadjusted for 3% inflation.Cooling Water0.28 $/mgal 0.23 1999EPA Air Pollution Control Cost Manual, 6thed. Section 3.1 Ch 1.Ch 1 Carbon Absorbers, 1999 $0.15 - $0.30 Avg of22.5 and 7 yrs and3% inflation.Compressed Air0.32 $/mscf 0.25 1998EPA Air Pollution Control Cost Manual 6th Ed2002, Section 6 Chapter 1 .Example problem; Dried & Filtered, Ch 1.6 '98 costadjusted for 3%inflation.Wastewater Disposal Neutralization1.69 $/mgal 1.50 2002EPA Air Pollution Control Cost Manual 6th Ed2002, Section 2 Chapter 2.5.5.5.Section 2 lists $1- $2/1000 gal. Cost adjusted for3% inflation Sec 6 Ch3 lists $1.30 - $2.15/1,000 gal.Chemicals & SuppliesLime88.98 $/ton 88.98 2006Estimate from Cutler-Magney Company.Oxygen40.00 $/ton2006BOC estimate.Ammonia (29% aqua.)0.12 $/lb0.101 2000EPA Air Pollution Control Cost Manual 6th Ed2002, Section 5 Chapter 2, page 2-50.Annual costs for a retrofit SCR system example problem. '00 costsadjusted for 3% inflation.Caustic305.96 $/ton280 2003 Hawkins Chemical50% solution (50 Deg Be); includes delivery. '03 cost adjusted for inflationOtherSales Tax6.5% %Interest Rate7.00% %EPA Air Pollution Control Cost ManualIntroduction, Chapter 2, section 2.4.2.Social (discount) rate used as a default.Operating InformationAnnual Op. Hrs8339.1 Hours2006Site Specific - Northshore Mining .Maximum hours of operation 2004-2005 with a 10% safety factor.Utilization Rate93%Equipment Life20 yrsEngineering Estimate.Standardized Flow RateSV 101, 102, & 103 181,762 scfm @ 32o FCalculated.SV 104 & 105 152,520 scfm @ 32o FCalculated.SV 111, 112, & 113 181,762 scfm @ 32o FCalculated.SV 114 & 115 152,520 scfm @ 32o FCalculated.Y:\23\00 MN Taconite BART (2006)\Facility BART Reports\NMC\NMC Furnace-Process Boiler\Appendices\Appendix A - NMC Control Costs.xlsUtility Chem$ Data9/6/2006 Page 2 of 56ReferenceItem Unit Cost Units Cost Year Data Source NotesTemperatureSV 101, 102, & 103 142 Deg FBART spreadsheet.SV 104 & 105 140 Deg FBART spreadsheet.SV 111, 112, & 113 142 Deg FBART spreadsheet.SV 114 & 115 140 Deg FBART spreadsheet.Moisture ContentSV 101, 102, & 103 11.3%2006Y:\23\38\126 NSM 2006 Stack Testing\WK4Fce 11+\Data. Average from test results in:Test 1-3Fce 11 HE 1101-1103 - 6-13-06.SV 104 & 105 18.3%2006Y:\23\38\126 NSM 2006 Stack Testing\WK4Fce 11+\Data. Average from test results in: Test 4-5Fce 11 WG 1104-1105 - 6-14-06.SV 111, 112, & 113 9.5%2006Y:\23\38\126 NSM 2006 Stack Testing\WK2Fce 12\Data. Average from test results in: Fce 12 HE1201-1203 4-18-06.SV 114 & 115 16.4%2006Y:\23\38\126 NSM 2006 Stack Testing\WK2Fce 12\Data.Average from test results in: Fce 12 WG 1204-1205 4-19-06.Actual Flow RateSV 101, 102, & 103 222,400 acfmBART spreadsheet.SV 104 & 105 186,000 acfmBART spreadsheet.SV 111, 112, & 113 222,400 acfmBART spreadsheet.SV 114 & 115 186,000 acfmBART spreadsheet.Standardized Flow RateSV 101, 102, & 103 195,062 scfm @ 68o FCalculated.SV 104 & 105 163,680 scfm @ 68o FCalculated.SV 111, 112, & 113 195,062 scfm @ 68o FCalculated.SV 114 & 115 163,680 scfm @ 68o FCalculated.Dry Std Flow RateSV 101, 102, & 103 172,951 dscfm @ 68o FCalculated.SV 104 & 105 133,792 dscfm @ 68o FCalculated.SV 111, 112, & 113 176,529 dscfm @ 68o FCalculated.SV 114 & 115 136,902 dscfm @ 68o FCalculated.Max Emis Actual Emissions lb/hr ton/yearPollutant Lb/Hr Ton/year ('04&'05 Max) ppmv ppmvNitrous Oxides (NOx)SV 101, 102, & 103 51.3 112.4 41 20.72005 plus 10%SV 104 & 105 124.8 273.7 130 65.12004 plus 10%SV 111, 112, & 113 51.3 109.9 40 19.82004 plus 10%SV 114 & 115 124.8 267.7 127 62.32004 plus 10%Sulfur Dioxides (SO2)SV 101, 102, & 103 35.5 28.6 21 3.82004 plus 10%SV 104 & 105 11.8 9.6 9 1.62004 plus 10%SV 111, 112, & 113 35.5 26.3 20 3.42004 plus 10%SV 114 & 115 11.8 8.8 9 1.52004 plus 10%guesscalculated valueknown or assumed datarequired dataY:\23\00 MN Taconite BART (2006)\Facility BART Reports\NMC\NMC Furnace-Process Boiler\Appendices\Appendix A - NMC Control Costs.xlsUtility Chem$ Data9/6/2006 Page 3 of 56

## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 3: SO x 

## Control - Wet Scrubber

Operating Unit: Furnace 11 Hood Exhaust

Emission Unit Number EU 100 Stack/Vent Number SV 101, 102, & 103 Standardized Flow Rate 181,762 scfm @ 32o F Expected Utilization Rate 93% Temperature 142 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 11.3% Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 172,951 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs (1) Purchased Equipment (A) 2,765,654 Purchased Equipment Total (B) 22% of control device cost (A) 3,360,270

Installation - Standard Costs 85% of purchased equi p cost (B) 2,856,229 Installation - Site Specific Costs 6,200,000 Installation Total 2,856,229 Total Direct Capital Cost, DC 6,216,499 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 504,040 Total Capital Investment (TCI) = DC + IC 16,952,864

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 476,790 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,924,559 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,401,349

Actual 

### Emission Control Cost Calculation Emis Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 51.3 112.4

0% 112.4 - NA Sulfur Dioxide (SO 2 ) 35.5 28.6

60% 11.4 17.2 139,872

Notes & Assumptions 1 Original estimate from STS Consultants. Use 0.6 Po wer law factor to adjust price to stack flow rate f rom bid basis of 500,000 acfm. 2 Liquid/Gas ratio = 38 L/G = Gal/1,000 acf. 3 Water Makeup Rate/Wastewater Discharge = 2.0% of ci rculating water rate. 4 Evaporation rate calculated from steam table in Bas ic Principles and Calculations in Chemical Engineer ing Third Edition. 5 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 3: SOx Control - Wet Scrubber

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxiliary equipment, EC 2,765,654 Instrumentation 10% of control device cost (A) 276,565 MN Sales Taxes 7% of control device cost (A) 179,768 Freight 5% of control device cost (A) 138,283 Purchased Equipment Total (B) 22% 3,360,270

Installation Foundations & supports 12% of purchased equip cost (B ) 403,232 Handling & erection 40% of purchased equip cost (B) 1,344,108 Electrical 1% of purchased equip cost (B) 33,603 Piping 30% of purchased equip cost (B) 1,008,081 Insulation 1% of purchased equip cost (B) 33,603 Painting 1% of purchased equip cost (B) 33,603 Installation Subtotal Standard Expenses 85% 2,856,229

Total Direct Capital Cost, DC 6,216,499

Indirect Capital Costs Engineering, supervision 5% of purchased equip cost (B) 168,013 Construction & field expenses 0% of purchased equip cost (B) 0 Contractor fees 5% of purchased equip cost (B) 168,013 Start-up 1% of purchased equip cost (B) 33,603 Performance test 1% of purchased equip cost (B) 33,603 Model Studies NA of purchased equip cost (B) NA Contingencies 3% of purchased equip cost (B) 100,808 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 504,040

Total Capital Investment (TCI) = DC + IC 6,720,540 Retrofit multiplier 5 60% of TCI 4,032,324

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 16,952,864



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 37.00 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hour s, 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 40.00 $/Hr, 0.5 hr/8 hr shift, Ann ual Operating Hours, 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 457 kW-hr, Annual Operating Hours, 93% u tilization 212,823 Water 0.28 $/kgal, 209 gpm, Annual Operating Hours, 93% ut ilization 26,883 WW Treat Neutralization 1.69 $/kgal, 169 gpm, Annual Operating Hours, 93% utilization 132,783 Lime 88.98 $/ton, 34 lb/hr, Annual Operating Hours, 93% u tilization 11,789 Total Annual Direct Operating Costs 476,790

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 134,411 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 67,205 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 67,205 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 1,600,230 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,924,559

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,401,349

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 3: SOx Control - Wet Scrubber

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Equipment Life 20 years CRF 0.0000 Rep part cost per unit 0 $/ft 3 Amount Required 0 ft 3 Packing Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst cost (basis labor f or baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0.00 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQ PS list replacement times from 5 - 20 min per bag. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm ∆ P in H2O Efficiency Hp kW Blower, Scrubber 222,400 8.55 0.7 - 317.8 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.48 Flow Liquid SPGR ∆ P ft H2O Efficiency Hp kW Circ Pump 8,451 gpm 1 60 0.7

- 136.2 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.49
H2O WW Disch 209 gpm 1 60 0.7 - 3.4 EPA Cost Cont Manual 6th ed Sectio n 5.2 Chapter 1 Eq 1.49 Other Total 457.4

Reagent Use & Other Operating Costs Caustic Use 35.50 lb/hr SO2 2.50 lb NaOH/lb SO2 88.75 lb/hr Caustic Lime Use 35.50 lb/hr SO2 0.96 lb Lime/lb SO2 34.17 lb/hr lime, lime addition at 1.1 times the sto ichiometric ratio Liquid/Gas ratio 38.0 * L/G = Gal/1,000 acf Circulating Water Rate 2 8,451 gpm Water Makeup Rate/WW Disch 3 = 2.0% of circulating water rate + evap. loss = 209 gpm Evaporation Loss 4 = 39.66 gpm

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, Annual Operating Hours, Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hours, Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 457.4 kW-hr 3,547,050 212,823 $/k wh, 457 kW-hr, Annual Operating Hours, 93% utilizat ion Water 0.28 $/kgal 208.7 gpm 97,104 26,883 $/kgal, 209 gpm , Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/kgal 169.0 gpm 78,651 132, 783 $/kgal, 169 gpm, Annual Operating Hours, 93% uti lization Lime 89.0 $/ton 34.2 lb/hr 132 11,789 $/ton, 34 lb/hr, Ann ual Operating Hours, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 4: SO x 

## Control - Wet Scrubber

Operating Unit: Furnace 11 Waste Gas

Emission Unit Number EU 104 Stack/Vent Number SV 104 & 105 Standardized Flow Rate 152,520 scfm @ 32o F Expected Utilization Rate 93% Temperature 140 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 18.3% Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 133,792 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs (1) Purchased Equipment (A) 2,484,419 Purchased Equipment Total (B) 22% of control device cost (A) 3,018,569

Installation - Standard Costs 85% of purchased equi p cost (B) 2,565,783 Installation - Site Specific Costs 6,200,000 Installation Total 2,565,783 Total Direct Capital Cost, DC 5,584,352 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 452,785 Total Capital Investment (TCI) = DC + IC 15,859,420

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 407,966 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,794,010 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,201,975

Actual 

### Emission Control Cost Calculation Emis Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 124.8 273.7

0% 273.7 - NA Sulfur Dioxide (SO 2 ) 11.8 9.6

60% 3.8 5.7 384,034

Notes & Assumptions 1 Original estimate from STS Consultants. Use 0.6 Po wer law factor to adjust price to stack flow rate f rom bid basis of 500,000 acfm. 2 Liquid/Gas ratio = 38 L/G = Gal/1,000 acf. 3 Water Makeup Rate/Wastewater Discharge = 2.0% of ci rculating water rate. 4 Evaporation rate calculated from steam table in Bas ic Principles and Calculations in Chemical Engineer ing Third Edition. 5 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 4: SOx Control - Wet Scrubber

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxiliary equipment, EC 2,484,419 Instrumentation 10% of control device cost (A) 248,442 MN Sales Taxes 7% of control device cost (A) 161,487 Freight 5% of control device cost (A) 124,221 Purchased Equipment Total (B) 22% 3,018,569

Installation Foundations & supports 12% of purchased equip cost (B ) 362,228 Handling & erection 40% of purchased equip cost (B) 1,207,427 Electrical 1% of purchased equip cost (B) 30,186 Piping 30% of purchased equip cost (B) 905,571 Insulation 1% of purchased equip cost (B) 30,186 Painting 1% of purchased equip cost (B) 30,186 Installation Subtotal Standard Expenses 85% 2,565,783

Total Direct Capital Cost, DC 5,584,352

Indirect Capital Costs Engineering, supervision 5% of purchased equip cost (B) 150,928 Construction & field expenses 0% of purchased equip cost (B) 0 Contractor fees 5% of purchased equip cost (B) 150,928 Start-up 1% of purchased equip cost (B) 30,186 Performance test 1% of purchased equip cost (B) 30,186 Model Studies NA of purchased equip cost (B) NA Contingencies 3% of purchased equip cost (B) 90,557 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 452,785

Total Capital Investment (TCI) = DC + IC 6,037,137 Retrofit multiplier 5 60% of TCI 3,622,282

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 15,859,420



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 37.00 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hour s, 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 40.00 $/Hr, 0.5 hr/8 hr shift, Ann ual Operating Hours, 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 383 kW-hr, Annual Operating Hours, 93% u tilization 177,990 Water 0.28 $/kgal, 175 gpm, Annual Operating Hours, 93% ut ilization 22,483 WW Treat Neutralization 1.69 $/kgal, 141 gpm, Annual Operating Hours, 93% utilization 111,050 Lime 88.98 $/ton, 11 lb/hr, Annual Operating Hours, 93% u tilization 3,930 Total Annual Direct Operating Costs 407,966

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 120,743 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 60,371 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 60,371 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 1,497,017 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,794,010

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,201,975

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 4: SOx Control - Wet Scrubber

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Equipment Life 20 years CRF 0.0000 Rep part cost per unit 0 $/ft 3 Amount Required 0 ft 3 Packing Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst cost (basis labor f or baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0.00 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQ PS list replacement times from 5 - 20 min per bag. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm ∆ P in H2O Efficiency Hp kW Blower, Scrubber 186,000 8.55 0.7 - 265.8 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.48 Flow Liquid SPGR ∆ P ft H2O Efficiency Hp kW Circ Pump 7,068 gpm 1 60 0.7

- 113.9 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.49
H2O WW Disch 175 gpm 1 60 0.7 - 2.8 EPA Cost Cont Manual 6th ed Sectio n 5.2 Chapter 1 Eq 1.49 Other Total 382.5

Reagent Use & Other Operating Costs Caustic Use 11.83 lb/hr SO2 2.50 lb NaOH/lb SO2 29.58 lb/hr Caustic Lime Use 11.83 lb/hr SO2 0.96 lb Lime/lb SO2 11.39 lb/hr lime, lime addition at 1.1 times the sto ichiometric ratio Liquid/Gas ratio 38.0 * L/G = Gal/1,000 acf Circulating Water Rate 2 7,068 gpm Water Makeup Rate/WW Disch 3 = 2.0% of circulating water rate + evap. loss = 175 gpm Evaporation Loss 4 = 33.17 gpm

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, Annual Operating Hours, Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hours, Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 382.5 kW-hr 2,966,507 177,990 $/k wh, 383 kW-hr, Annual Operating Hours, 93% utilizat ion Water 0.28 $/kgal 174.5 gpm 81,211 22,483 $/kgal, 175 gpm , Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/kgal 141.4 gpm 65,778 111,050 $/kgal, 141 gpm, Ann ual Operating Hours, 93% utilization Lime 89.0 $/ton 11.4 lb/hr 44 3,930 $/ton, 11 lb/hr, Annua l Operating Hours, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 5 SO x 

## Control - Wet Scrubber

Operating Unit: Furnace 12 Hood Exhaust

Emission Unit Number EU 110 Stack/Vent Number SV 111, 112, & 113 Standardized Flow Rate 181,762 scfm @ 32o F Expected Utilization Rate 93% Temperature 142 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 9.5% Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 176,529 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs (1) Purchased Equipment (A) 2,765,654 Purchased Equipment Total (B) 22% of control device cost (A) 3,360,270

Installation - Standard Costs 85% of purchased equi p cost (B) 2,856,229 Installation - Site Specific Costs 6,200,000 Installation Total 2,856,229 Total Direct Capital Cost, DC 6,216,499 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 504,040 Total Capital Investment (TCI) = DC + IC 16,952,864

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 476,790 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,924,559 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,401,349

Actual 

### Emission Control Cost Calculation Emis Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 51.3 109.9

0% 109.9 - NA Sulfur Dioxide (SO 2 ) 35.5 26.3

60% 10.5 15.8 152,149

Notes & Assumptions 1 Original estimate from STS Consultants. Use 0.6 Po wer law factor to adjust price to stack flow rate f rom bid basis of 500,000 acfm. 2 Liquid/Gas ratio = 38 L/G = Gal/1,000 acf. 3 Water Makeup Rate/Wastewater Discharge = 2.0% of ci rculating water rate. 4 Evaporation rate calculated from steam table in Bas ic Principles and Calculations in Chemical Engineer ing Third Edition. 5 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 5 SOx Control - Wet Scrubber

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxiliary equipment, EC 2,765,654 Instrumentation 10% of control device cost (A) 276,565 MN Sales Taxes 7% of control device cost (A) 179,768 Freight 5% of control device cost (A) 138,283 Purchased Equipment Total (B) 22% 3,360,270

Installation Foundations & supports 12% of purchased equip cost (B ) 403,232 Handling & erection 40% of purchased equip cost (B) 1,344,108 Electrical 1% of purchased equip cost (B) 33,603 Piping 30% of purchased equip cost (B) 1,008,081 Insulation 1% of purchased equip cost (B) 33,603 Painting 1% of purchased equip cost (B) 33,603 Installation Subtotal Standard Expenses 85% 2,856,229

Total Direct Capital Cost, DC 6,216,499

Indirect Capital Costs Engineering, supervision 5% of purchased equip cost (B) 168,013 Construction & field expenses 0% of purchased equip cost (B) 0 Contractor fees 5% of purchased equip cost (B) 168,013 Start-up 1% of purchased equip cost (B) 33,603 Performance test 1% of purchased equip cost (B) 33,603 Model Studies NA of purchased equip cost (B) NA Contingencies 3% of purchased equip cost (B) 100,808 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 504,040

Total Capital Investment (TCI) = DC + IC 6,720,540 Retrofit multiplier 5 60% of TCI 4,032,324

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 16,952,864



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 37.00 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hour s, 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 40.00 $/Hr, 0.5 hr/8 hr shift, Ann ual Operating Hours, 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 457 kW-hr, Annual Operating Hours, 93% u tilization 212,823 Water 0.28 $/kgal, 209 gpm, Annual Operating Hours, 93% ut ilization 26,883 WW Treat Neutralization 1.69 $/kgal, 169 gpm, Annual Operating Hours, 93% utilization 132,783 Lime 88.98 $/ton, 34 lb/hr, Annual Operating Hours, 93% u tilization 11,789 Total Annual Direct Operating Costs 476,790

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 134,411 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 67,205 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 67,205 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 1,600,230 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,924,559

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,401,349

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 5 SOx Control - Wet Scrubber

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Equipment Life 20 years CRF 0.0000 Rep part cost per unit 0 $/ft 3 Amount Required 0 ft 3 Packing Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst cost (basis labor f or baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0.00 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQ PS list replacement times from 5 - 20 min per bag. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm ∆ P in H2O Efficiency Hp kW Blower, Scrubber 222,400 8.55 0.7 - 317.8 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.48 Flow Liquid SPGR ∆ P ft H2O Efficiency Hp kW Circ Pump 8,451 gpm 1 60 0.7

- 136.2 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.49
H2O WW Disch 209 gpm 1 60 0.7 - 3.4 EPA Cost Cont Manual 6th ed Sectio n 5.2 Chapter 1 Eq 1.49 Other Total 457.4

Reagent Use & Other Operating Costs Caustic Use 35.50 lb/hr SO2 2.50 lb NaOH/lb SO2 88.75 lb/hr Caustic Lime Use 35.50 lb/hr SO2 0.96 lb Lime/lb SO2 34.17 lb/hr lime, lime addition at 1.1 times the sto ichiometric ratio Liquid/Gas ratio 38.0 * L/G = Gal/1,000 acf Circulating Water Rate 2 8,451 gpm Water Makeup Rate/WW Disch 3 = 2.0% of circulating water rate + evap. loss = 209 gpm Evaporation Loss 4 = 39.66 gpm

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, Annual Operating Hours, Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hours, Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 457.4 kW-hr 3,547,050 212,823 $/k wh, 457 kW-hr, Annual Operating Hours, 93% utilizat ion Water 0.28 $/kgal 208.7 gpm 97,104 26,883 $/kgal, 209 gpm , Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/kgal 169.0 gpm 78,651 132,783 $/kgal, 169 gpm, Ann ual Operating Hours, 93% utilization Lime 89.0 $/ton 34.2 lb/hr 132 11,789 $/ton, 34 lb/hr, Ann ual Operating Hours, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 6: SO x 

## Control - Wet Scrubber

Operating Unit: Furnace 12 Waste Gas

Emission Unit Number EU 114 Stack/Vent Number SV 114 & 115 Standardized Flow Rate 152,520 scfm @ 32o F Expected Utilization Rate 93% Temperature 140 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 16.4% Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 136,902 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs (1) Purchased Equipment (A) 2,484,419 Purchased Equipment Total (B) 22% of control device cost (A) 3,018,569

Installation - Standard Costs 85% of purchased equi p cost (B) 2,565,783 Installation - Site Specific Costs 6,200,000 Installation Total 2,565,783 Total Direct Capital Cost, DC 5,584,352 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 452,785 Total Capital Investment (TCI) = DC + IC 15,859,420

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 407,966 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,794,010 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,201,975

Actual 

### Emission Control Cost Calculation Emis Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 124.8 267.7

0% 267.7 - NA Sulfur Dioxide (SO 2 ) 11.8 8.8

60% 3.5 5.3 417,742

Notes & Assumptions 1 Original estimate from STS Consultants. Use 0.6 Po wer law factor to adjust price to stack flow rate f rom bid basis of 500,000 acfm. 2 Liquid/Gas ratio = 38 L/G = Gal/1,000 acf. 3 Water Makeup Rate/Wastewater Discharge = 2.0% of ci rculating water rate. 4 Evaporation rate calculated from steam table in Bas ic Principles and Calculations in Chemical Engineer ing Third Edition. 5 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 6: SOx Control - Wet Scrubber

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxiliary equipment, EC 2,484,419 Instrumentation 10% of control device cost (A) 248,442 MN Sales Taxes 7% of control device cost (A) 161,487 Freight 5% of control device cost (A) 124,221 Purchased Equipment Total (B) 22% 3,018,569

Installation Foundations & supports 12% of purchased equip cost (B ) 362,228 Handling & erection 40% of purchased equip cost (B) 1,207,427 Electrical 1% of purchased equip cost (B) 30,186 Piping 30% of purchased equip cost (B) 905,571 Insulation 1% of purchased equip cost (B) 30,186 Painting 1% of purchased equip cost (B) 30,186 Installation Subtotal Standard Expenses 85% 2,565,783

Total Direct Capital Cost, DC 5,584,352

Indirect Capital Costs Engineering, supervision 5% of purchased equip cost (B) 150,928 Construction & field expenses 0% of purchased equip cost (B) 0 Contractor fees 5% of purchased equip cost (B) 150,928 Start-up 1% of purchased equip cost (B) 30,186 Performance test 1% of purchased equip cost (B) 30,186 Model Studies NA of purchased equip cost (B) NA Contingencies 3% of purchased equip cost (B) 90,557 Total Indirect Capital Costs, IC 15% of purchased equip cost (B) 452,785

Total Capital Investment (TCI) = DC + IC 6,037,137 Retrofit multiplier 5 60% of TCI 3,622,282

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 15,859,420



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 37.00 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hour s, 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 40.00 $/Hr, 0.5 hr/8 hr shift, Ann ual Operating Hours, 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 383 kW-hr, Annual Operating Hours, 93% u tilization 177,990 Water 0.28 $/kgal, 175 gpm, Annual Operating Hours, 93% ut ilization 22,483 WW Treat Neutralization 1.69 $/kgal, 141 gpm, Annual Operating Hours, 93% utilization 111,050 Lime 88.98 $/ton, 11 lb/hr, Annual Operating Hours, 93% u tilization 3,930 Total Annual Direct Operating Costs 407,966

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 120,743 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 60,371 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 60,371 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 1,497,017 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,794,010

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 2,201,975

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 6: SOx Control - Wet Scrubber

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Equipment Life 20 years CRF 0.0000 Rep part cost per unit 0 $/ft 3 Amount Required 0 ft 3 Packing Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst cost (basis labor f or baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0.00 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQ PS list replacement times from 5 - 20 min per bag. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm ∆ P in H2O Efficiency Hp kW Blower, Scrubber 186,000 8.55 0.7 - 265.8 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.48 Flow Liquid SPGR ∆ P ft H2O Efficiency Hp kW Circ Pump 7,068 gpm 1 60 0.7

- 113.9 EPA Cost Cont Manual 6th ed Section 5.2 Chapter 1 Eq 1.49
H2O WW Disch 175 gpm 1 60 0.7 - 2.8 EPA Cost Cont Manual 6th ed Sectio n 5.2 Chapter 1 Eq 1.49 Other Total 382.5

Reagent Use & Other Operating Costs Caustic Use 11.83 lb/hr SO2 2.50 lb NaOH/lb SO2 29.58 lb/hr Caustic Lime Use 11.83 lb/hr SO2 0.96 lb Lime/lb SO2 11.39 lb/hr lime, lime addition at 1.1 times the sto ichiometric ratio Liquid/Gas ratio 38.0 * L/G = Gal/1,000 acf Circulating Water Rate 2 7,068 gpm Water Makeup Rate/WW Disch 3 = 2.0% of circulating water rate + evap. loss = 175 gpm Evaporation Loss 4 = 33.17 gpm

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, Annual Operating Hours, Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, Annual Operating Hours, Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 382.5 kW-hr 2,966,507 177,990 $/k wh, 383 kW-hr, Annual Operating Hours, 93% utilizat ion Water 0.28 $/kgal 174.5 gpm 81,211 22,483 $/kgal, 175 gpm , Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/kgal 141.4 gpm 65,778 111,050 $/kgal, 141 gpm, Ann ual Operating Hours, 93% utilization Lime 89.0 $/ton 11.4 lb/hr 44 3,930 $/ton, 11 lb/hr, Annua l Operating Hours, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 7: SO 2 

## Control - Wet Walled Electrostatic Precipitator

Operating Unit: Furnace 11 Hood Exhaust

Emission Unit Number EU 100 Stack/Vent Number SV 101, 102, & 103 Standardized Flow Rate 181,762 scfm @ 32o F Expected Utilization Rate 93% Temperature 142 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 11.3% Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 172,951 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 3,999,843 Purchased Equipment Total (B) 22% of control device cost (A) 4,859,809

Installation - Standard Costs 67% of purchased equi p cost (B) 3,256,072 Installation - Site Specific Costs 6,200,000 Installation Total 3,256,072 Total Direct Capital Cost, DC 8,115,881 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,770,091 Total Capital Investment (TCI) = DC + IC 23,617,556

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 1,425,578 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,763,297 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,188,875

Actual 

### Emission Control Cost Calculation Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 51.3 112.4

0% 112.4 - NA Sulfur Dioxide (SO 2 ) 35.5 28.6

80% 5.7 22.9 182,993

Notes & Assumptions 1 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 6 Chapter 3. 2 Original estimate from Durr. Used 0.6 power law fa ctor to adjust price to stack flow rate acfm from b id basis of 291,000 acfm. 3 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 7: SO2 Control - Wet Walled Electrostatic Pre cipitator

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) 1 Purchased Equipment Costs (A) 2 - ESP + auxiliary equipment 3,999,843 Instrumentation 10% of control device cost (A) 399,984 MN Sales Taxes 6.5% of control device cost (A) 259,990 Freight 5% of control device cost (A) 199,992 Purchased Equipment Total (B) 22% 4,859,809

Installation Foundations & supports 4% of purchased equip cost (B) 194,392 Handling & erection 50% of purchased equip cost (B) 2,429,905 Electrical 8% of purchased equip cost (B) 388,785 Piping 1% of purchased equip cost (B) 48,598 Insulation 2% of purchased equip cost (B) 97,196 Painting 2% of purchased equip cost (B) 97,196 Installation Subtotal Standard Expenses 67% 3,256,072

Total Direct Capital Cost, DC 8,115,881

Indirect Capital Costs Engineering, supervision 20% of purchased equip cost (B) 971,962 Construction & field expenses 20% of purchased equip cost (B) 971,962 Contractor fees 10% of purchased equip cost (B) 485,981 Start-up 1% of purchased equip cost (B) 48,598 Performance test 1% of purchased equip cost (B) 48,598 Model Studies 2% of purchased equip cost (B) 97,196 Contingencies 3% of purchased equip cost (B) 145,794 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,770,091

Total Capital Investment (TCI) = DC + IC 10,885,972 Retrofit multiplier 3 60% of TCI 6,531,583

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific NA Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 23,617,556



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2 hr/8 hr shift, Annual Operating Hours, 0% utilization 104,239 Supervisor 15% of Op., 0 , Annual Operating Hours, 0% utilizati on 15,636 Maintenance Maintenance Labor 60.00 $/Hr, 15 hr/wk, Annual Opera ting Hours, 0% utilization 4,340 Maintenance Materials 1.00 % of Maintenance Labor 39,998 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 526 kW-hr, Annual Operating Hours, 93% u tilization 244,544 Water 0.28 $/mgal, 1,112 gpm, Annual Operating Hours, 93% utilization 143,251 WW Treat Neutralization 1.69 $/mgal, 1,112 gpm, Annua l Operating Hours, 93% utilization 873,571 Caustic 305.96 $/ton, 89 lb/hr, 8339.1 hr/yr, 93% utilizatio n 105,296 Total Annual Direct Operating Costs 1,425,578

Indirect Operating Costs Overhead 60% of total labor and material costs 98,528 Administration (2% total capital costs) 2% of total c apital costs (TCI) 217,719 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 108,860 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 108,860 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 2,229,330 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,763,297

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,188,875

See summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 7: SO2 Control - Wet Walled Electrostatic Pre cipitator

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit Amount Required 0 Total Rep Parts Cost 0 Installation Labor 0 Total Installed Cost 0 Annualized Cost 0

Electrical Use Flow acfm D P in H2O kW Fan Power 222,400 10 402.5 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.46 Fluid Head (ft) Pump Eff. Pump Power 60 60% 20.9 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.47
Plate Area ESP Power 52,600 102.0 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.48

Total 525.5

Reagent Use & Other Operating Costs

gpm Water 5.00 gal/min-kacfm 1112.00 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1 .6

lb/hr Reagent Use 2.50 lb NaOH/lb SO2 88.75 lb/hr caustic

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93.0%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor , 0 , Annual Operating Hours, 0% utilization Op Labor 50 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2 hr/8 hr shift, Annual Operating Hours, 0% utilizati on Supervisor 15% of Op. NA 15,636 of Op., 0 , Annual Operating Hours, 0% uti lization Maintenance , 0 , Annual Operating Hours, 0% utilization Maint Labor 60.00 $/Hr 15.0 hr/wk 660 4,340 $/Hr, 15 hr/w k, Annual Operating Hours, 0% utilization Maint Mtls 1 % of Purchase Cost NA 39,998 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1.1 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 525.5 kW-hr 4,075,729 244,544 $/kwh, 526 kW-hr, Annual Operating Hours, 93% utili zation Water 0.28 $/mgal 1,112.0 gpm 517,438 143,251 $/mgal, 1,1 12 gpm, Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/mgal 1,112.0 gpm 517,438 873,571 $/mgal, 1,112 gpm , Annual Operating Hours, 93% utilization Caustic 305.96 $/ton 88.8 lb/hr 344 105,296 $/ton, 89 lb/h r, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 8: SO 2 

## Control - Wet Walled Electrostatic Precipitator

Operating Unit: Furnace 11 Waste Gas

Emission Unit Number EU 104 Stack/Vent Number SV 104 & 105 Standardized Flow Rate 152,520 scfm @ 32o F Expected Utilization Rate 93% Temperature 140 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 18.3% Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 133,792 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 3,593,104 Purchased Equipment Total (B) 22% of control device cost (A) 4,365,622

Installation - Standard Costs 67% of purchased equi p cost (B) 2,924,967 Installation - Site Specific Costs 6,200,000 Installation Total 2,924,967 Total Direct Capital Cost, DC 7,290,588 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,488,404 Total Capital Investment (TCI) = DC + IC 21,846,389

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 1,249,949 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,549,263 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,799,211

Actual 

### Emission Control Cost Calculation Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 124.8 273.7

0% 273.7 - NA Sulfur Dioxide (SO 2 ) 11.8 9.6

80% 1.9 7.6 496,949

Notes & Assumptions 1 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 6 Chapter 3. 2 Original estimate from Durr. Used 0.6 power law fa ctor to adjust price to stack flow rate acfm from b id basis of 291,000 acfm. 3 CUECost Workbook Version 1.0, USEPA Document Page 2

.

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 8: SO2 Control - Wet Walled Electrostatic Pre cipitator

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) 1 Purchased Equipment Costs (A) 2 - ESP + auxiliary equipment 3,593,104 Instrumentation 10% of control device cost (A) 359,310 MN Sales Taxes 6.5% of control device cost (A) 233,552 Freight 5% of control device cost (A) 179,655 Purchased Equipment Total (B) 22% 4,365,622

Installation Foundations & supports 4% of purchased equip cost (B) 174,625 Handling & erection 50% of purchased equip cost (B) 2,182,811 Electrical 8% of purchased equip cost (B) 349,250 Piping 1% of purchased equip cost (B) 43,656 Insulation 2% of purchased equip cost (B) 87,312 Painting 2% of purchased equip cost (B) 87,312 Installation Subtotal Standard Expenses 67% 2,924,967

Total Direct Capital Cost, DC 7,290,588

Indirect Capital Costs Engineering, supervision 20% of purchased equip cost (B) 873,124 Construction & field expenses 20% of purchased equip cost (B) 873,124 Contractor fees 10% of purchased equip cost (B) 436,562 Start-up 1% of purchased equip cost (B) 43,656 Performance test 1% of purchased equip cost (B) 43,656 Model Studies 2% of purchased equip cost (B) 87,312 Contingencies 3% of purchased equip cost (B) 130,969 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,488,404

Total Capital Investment (TCI) = DC + IC 9,778,993 Retrofit multiplier 3 60% of TCI 5,867,396

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific NA Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 21,846,389



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Labor 60.00 $/Hr, 15.0 hr/wk, 8339.1 hr/ yr 4,125 Maintenance Materials 1.00 % of Maintenance Labor 35,931 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 440 kW-hr, Annual Operating Hours, 93% u tilization 204,519 Water 0.28 $/mgal, 930 gpm, Annual Operating Hours, 93% ut ilization 119,805 WW Treat Neutralization 1.69 $/mgal, 930 gpm, Annual Operating Hours, 93% utilization 730,595 Caustic 305.96 $/ton, 30 lb/hr, 8339.1 hr/yr, 93% utilizatio n 35,099 Total Annual Direct Operating Costs 1,249,949

Indirect Operating Costs Overhead 60% of total labor and material costs 95,958 Administration (2% total capital costs) 2% of total c apital costs (TCI) 195,580 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 97,790 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 97,790 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 2,062,145 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,549,263

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,799,211

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU104 WWESP 9/6/2006 Page 20 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 8: SO2 Control - Wet Walled Electrostatic Pre cipitator

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit Amount Required 0 Total Rep Parts Cost 0 Installation Labor 0 Total Installed Cost 0 Annualized Cost 0

Electrical Use Flow acfm D P in H2O kW Fan Power 186,000 10 336.7 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.46 Fluid Head (ft) Pump Eff. Pump Power 60 60% 17.5 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.47
Plate Area ESP Power 43,991 85.3 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3. 48

Total 439.5

Reagent Use & Other Operating Costs

gpm Water 5.00 gal/min-kacfm 930.00 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1. 6

lb/hr Reagent Use 2.50 lb NaOH/lb SO2 29.58 lb/hr caustic

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93.0%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2. 0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 15.0 hr/wk 660 4,125 $/Hr, 15.0 hr /wk, 8339.1 hr/yr Maint Mtls 1 % of Purchase Cost NA 35,931 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1.1 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 439.5 kW-hr 3,408,658 204,519 $/kwh, 440 kW-hr, Annual Operating Hours, 93% utili zation Water 0.28 $/mgal 930.0 gpm 432,749 119,805 $/mgal, 930 g pm, Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/mgal 930.0 gpm 432,749 730,595 $/mgal, 930 gpm, An nual Operating Hours, 93% utilization Caustic 305.96 $/ton 29.6 lb/hr 115 35,099 $/ton, 30 lb/hr , 8339.1 hr/yr, 93% utilization *annual use rate is in same units of measurement as the unit cost factor

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU104 WWESP 9/6/2006 Page 21 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 9: SO 2 

## Control - Wet Walled Electrostatic Precipitator

Operating Unit: Furnace 12 Hood Exhaust

Emission Unit Number EU 110 Stack/Vent Number SV 111, 112, & 113 Standardized Flow Rate 181,762 scfm @ 32o F Expected Utilization Rate 93% Temperature 142 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 9.5% Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 176,529 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 3,999,843 Purchased Equipment Total (B) 22% of control device cost (A) 4,859,809

Installation - Standard Costs 67% of purchased equi p cost (B) 3,256,072 Installation - Site Specific Costs 6,200,000 Installation Total 3,256,072 Total Direct Capital Cost, DC 8,115,881 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,770,091 Total Capital Investment (TCI) = DC + IC 23,617,556

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 1,530,874 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,763,297 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,294,171

Actual 

### Emission Control Cost Calculation Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 51.3 109.9

0% 109.9 - NA Sulfur Dioxide (SO 2 ) 35.5 26.3

80% 5.3 21.0 204,058

Notes & Assumptions 1 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 6 Chapter 3. 2 Original estimate from Durr. Used 0.6 power law fa ctor to adjust price to stack flow rate acfm from b id basis of 291,000 acfm. 3 CUECost Workbook Version 1.0, USEPA Document Page 2

.

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU110 WWESP 9/6/2006 Page 22 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 9: SO2 Control - Wet Walled Electrostatic Pre cipitator

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) 1 Purchased Equipment Costs (A) 2 - ESP + auxiliary equipment 3,999,843 Instrumentation 10% of control device cost (A) 399,984 MN Sales Taxes 6.5% of control device cost (A) 259,990 Freight 5% of control device cost (A) 199,992 Purchased Equipment Total (B) 22% 4,859,809

Installation Foundations & supports 4% of purchased equip cost (B) 194,392 Handling & erection 50% of purchased equip cost (B) 2,429,905 Electrical 8% of purchased equip cost (B) 388,785 Piping 1% of purchased equip cost (B) 48,598 Insulation 2% of purchased equip cost (B) 97,196 Painting 2% of purchased equip cost (B) 97,196 Installation Subtotal Standard Expenses 67% 3,256,072

Total Direct Capital Cost, DC 8,115,881

Indirect Capital Costs Engineering, supervision 20% of purchased equip cost (B) 971,962 Construction & field expenses 20% of purchased equip cost (B) 971,962 Contractor fees 10% of purchased equip cost (B) 485,981 Start-up 1% of purchased equip cost (B) 48,598 Performance test 1% of purchased equip cost (B) 48,598 Model Studies 2% of purchased equip cost (B) 97,196 Contingencies 3% of purchased equip cost (B) 145,794 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,770,091

Total Capital Investment (TCI) = DC + IC 10,885,972 Retrofit multiplier 3 60% of TCI 6,531,583

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific NA Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 23,617,556



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Labor 60.00 $/Hr, 15.0 hr/wk, 8339.1 hr/ yr 4,340 Maintenance Materials 1.00 % of Maintenance Labor 39,998 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 526 kW-hr, Annual Operating Hours, 93% u tilization 244,544 Water 0.28 $/mgal, 1,112 gpm, Annual Operating Hours, 93% utilization 143,251 WW Treat Neutralization 1.69 $/mgal, 1,112 gpm, Annua l Operating Hours, 93% utilization 873,571 Caustic 305.96 $/ton, 89 lb/hr, 8339.1 hr/yr, 93% utilizatio n 105,296 Total Annual Direct Operating Costs 1,530,874

Indirect Operating Costs Overhead 60% of total labor and material costs 98,528 Administration (2% total capital costs) 2% of total c apital costs (TCI) 217,719 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 108,860 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 108,860 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 2,229,330 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,763,297

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,294,171

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU110 WWESP 9/6/2006 Page 23 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 9: SO2 Control - Wet Walled Electrostatic Pre cipitator

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit Amount Required 0 Total Rep Parts Cost 0 Installation Labor 0 Total Installed Cost 0 Annualized Cost 0

Electrical Use Flow acfm D P in H2O kW Fan Power 222,400 10 402.5 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.46 Fluid Head (ft) Pump Eff. Pump Power 60 60% 20.9 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.47
Plate Area ESP Power 52,600 102.0 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.48

Total 525.5

Reagent Use & Other Operating Costs

gpm Water 5.00 gal/min-kacfm 1112.00 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1 .6

lb/hr Reagent Use 2.50 lb NaOH/lb SO2 88.75 lb/hr caustic

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93.0%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2. 0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 15.0 hr/wk 660 4,340 $/Hr, 15.0 hr /wk, 8339.1 hr/yr Maint Mtls 1 % of Purchase Cost NA 39,998 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1.1 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 525.5 kW-hr 4,075,729 244,544 $/kwh, 526 kW-hr, Annual Operating Hours, 93% utili zation Water 0.28 $/mgal 1,112.0 gpm 517,438 143,251 $/mgal, 1,1 12 gpm, Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/mgal 1,112.0 gpm 517,438 873,571 $/mgal, 1,112 gpm , Annual Operating Hours, 93% utilization Caustic 305.96 $/ton 88.8 lb/hr 344 105,296 $/ton, 89 lb/h r, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU110 WWESP 9/6/2006 Page 24 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 10: SO 2 

## Control - Wet Walled Electrostatic Precipitator

Operating Unit: Furnace 12 Waste Gas

Emission Unit Number EU 114 Stack/Vent Number SV 114 & 115 Standardized Flow Rate 152,520 scfm @ 32o F Expected Utilization Rate 93% Temperature 140 Deg F Expected Annual Hours of Operation 8,339 Hours Moistur e Content 16.4% Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 136,902 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 3,593,104 Purchased Equipment Total (B) 22% of control device cost (A) 4,365,622

Installation - Standard Costs 67% of purchased equi p cost (B) 2,924,967 Installation - Site Specific Costs 6,200,000 Installation Total 2,924,967 Total Direct Capital Cost, DC 7,290,588 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,488,404 Total Capital Investment (TCI) = DC + IC 21,846,389

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 1,214,850 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,549,263 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,764,113

Actual 

### Emission Control Cost Calculation Emissions Max Emis Annual Cont Eff Cont Emis Reduction Cont Cost Pollutant Lb/Hr T/Yr % T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 124.8 267.7

0% 267.7 - NA Sulfur Dioxide (SO 2 ) 11.8 8.8

80% 1.8 7.0 535,575

Notes & Assumptions 1 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 6 Chapter 3. 2 Original estimate from Durr. Used 0.6 power law fa ctor to adjust price to stack flow rate acfm from b id basis of 291,000 acfm. 3 CUECost Workbook Version 1.0, USEPA Document Page 2

.

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU114 WWESP 9/6/2006 Page 25 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 10: SO2 Control - Wet Walled Electrostatic Pr ecipitator

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) 1 Purchased Equipment Costs (A) 2 - ESP + auxiliary equipment 3,593,104 Instrumentation 10% of control device cost (A) 359,310 MN Sales Taxes 6.5% of control device cost (A) 233,552 Freight 5% of control device cost (A) 179,655 Purchased Equipment Total (B) 22% 4,365,622

Installation Foundations & supports 4% of purchased equip cost (B) 174,625 Handling & erection 50% of purchased equip cost (B) 2,182,811 Electrical 8% of purchased equip cost (B) 349,250 Piping 1% of purchased equip cost (B) 43,656 Insulation 2% of purchased equip cost (B) 87,312 Painting 2% of purchased equip cost (B) 87,312 Installation Subtotal Standard Expenses 67% 2,924,967

Total Direct Capital Cost, DC 7,290,588

Indirect Capital Costs Engineering, supervision 20% of purchased equip cost (B) 873,124 Construction & field expenses 20% of purchased equip cost (B) 873,124 Contractor fees 10% of purchased equip cost (B) 436,562 Start-up 1% of purchased equip cost (B) 43,656 Performance test 1% of purchased equip cost (B) 43,656 Model Studies 2% of purchased equip cost (B) 87,312 Contingencies 3% of purchased equip cost (B) 130,969 Total Indirect Capital Costs, IC 57% of purchased equip cost (B) 2,488,404

Total Capital Investment (TCI) = DC + IC 9,778,993 Retrofit multiplier 3 60% of TCI 5,867,396

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific NA Total Site Specific Costs 6,200,000

Total Capital Investment (TCI) Retrofit Installed 21,846,389



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Labor 60.00 $/Hr, 15.0 hr/wk, 8339.1 hr/ yr 4,125 Maintenance Materials 1.00 % of Maintenance Labor 35,931 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 440 kW-hr, Annual Operating Hours, 93% u tilization 204,519 Water 0.28 $/mgal, 930 gpm, Annual Operating Hours, 93% ut ilization 119,805 WW Treat Neutralization 1.69 $/mgal, 930 gpm, Annual Operating Hours, 93% utilization 730,595 Total Annual Direct Operating Costs 1,214,850

Indirect Operating Costs Overhead 60% of total labor and material costs 95,958 Administration (2% total capital costs) 2% of total c apital costs (TCI) 195,580 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 97,790 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 97,790 Capital Recovery 0.0944 for a 20- year equipment life and a 7% intere st rate 2,062,145 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 2,549,263

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,764,113

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU114 WWESP 9/6/2006 Page 26 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 10: SO2 Control - Wet Walled Electrostatic Pr ecipitator

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit Amount Required 0 Total Rep Parts Cost 0 Installation Labor 0 Total Installed Cost 0 Annualized Cost 0

Electrical Use Flow acfm D P in H2O kW Fan Power 186,000 10 336.7 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.46 Fluid Head (ft) Pump Eff. Pump Power 60 60% 17.5 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3.47
Plate Area ESP Power 43,991 85.3 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3 Eq 3. 48

Total 439.5

Reagent Use & Other Operating Costs

gpm Water 5.00 gal/min-kacfm 930.00 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1. 6

lb/hr Reagent Use 2.50 lb NaOH/lb SO2 29.58 lb/hr caustic

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93.0%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2. 0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 15.0 hr/wk 660 4,125 $/Hr, 15.0 hr /wk, 8339.1 hr/yr Maint Mtls 1 % of Purchase Cost NA 35,931 EPA Cont Cost Manual 6th ed - Sec 6 Ch 3.4.1.1 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 439.5 kW-hr 3,408,658 204,519 $/k wh, 440 kW-hr, Annual Operating Hours, 93% utilizat ion Water 0.28 $/mgal 930.0 gpm 432,749 119,805 $/mgal, 930 g pm, Annual Operating Hours, 93% utilization WW Treat Neutralization 1.69 $/mgal 930.0 gpm 432,749 730,595 $/mgal, 930 gpm, An nual Operating Hours, 93% utilization Caustic 305.96 $/ton 29.6 lb/hr 115 35,099 $/ton, 30 lb/hr , 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls EU114 WWESP 9/6/2006 Page 27 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 11: - SCR + Reheat (100)

Operating Unit: Furnace 11 Hood Exhaust

Emission Unit Number EU 100 Stack/Vent Number SV 101, 102, & 103 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 181,762 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 142 Deg F 1998/1999 390 Expected Annual Hours of Operation 8,339 Hours Moisture Content 11.3% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 195,062 scfm @ 68o F Dry Std Flow Rate 172,951 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs EPRI Correlation Purchased Equipment (A) 10,191,798 Purchased Equipment Total (B) SCR Only 10,854,265

Installation - Standard Costs 15% of purchased equi p cost (B) SCR Only 2,024,725 Installation - Site Specific Costs 0 Installation Total 0 Total Direct Capital Cost, DC 0 Total Indirect Capital Costs, IC 0% of purchased equip cost (B) 0 Total Capital Investment (TCI) = DC + IC SCR + Reheat 46,019,283

Operating Costs Total Annual Direct Operating Costs Labor, supervision, materials, replacement parts, u tilities, etc. SCR + Reheat 7,301,482 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost SCR + Reheat 4,326,542 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) SCR + Reheat 11,628,024



### Emission Control Cost Calculation Baseline Predicted Limit Cont. Emis. Cont Emis Reduct ion Cont Cost Pollutant Emis. T/yr lb/hr lb/MMBtu T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 112.4 1.5

0.01

5.7 106.7 108,969

Notes & Assumptions 1 Estimated Equipment Cost per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2. 2 For Calculation purposes, duty reflects increased f low rate, not actual duty. 3 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 4 Capital Cost per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.36 -2.4 3 5 Reagent Use per EPA Air Pollution Control Cost Manu al 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.32 - 2.3 5 6 SCR Catalyst Volume per EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2. 18 - 2.24 7 SCR Reactor Size per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.25 - 2.31 8 SCR Catalyst Replacement per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.50 - 2.53 9 SCR Electrical Demand per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.48 10 SCR Maintenance Costs EPA Air Pollution Control Cos t Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.46 11 Control Efficiency = 90% reduction which is typical ly the upper range of normal SCR control efficiency 12 $35/MW-hr, 140 MW 13 Catalyst replacement every 8000 hours. This requir es an additional 2 week outage per 3 year outage cy cle, annualized to 4.7 days.

Notes to User

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (100) NOx SCR+ Reheat 90% Eff (100) 28 of 56

## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 11: - SCR + Reheat (100)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC 10,191,798 Instrumentation 10% of control device cost (A) NA MN Sales Taxes 6.5% of control device cost (A) 662,467 Freight 5% of control device cost (A) NA Purchased Equipment Total (A) 10,854,265

Indirect Installation General Facilities 0% of purchased equip cost (A) 0 Engineering & Home Office 0% of purchased equip cost (A) 0 Process Contingency 0% of purchased equip cost (A) 0 Site Specific-Other 24% Replacement Power, two weeks 2,643,899

Total Indirect Installation Costs (B) 24% of purchased equip cost (A) 2,643,899

Project Contingeny ( C) 15% of (A + B) 2,024,725

Total Plant Cost D A + B + C 15,522,888

Allowance for Funds During Construction (E) Additional 10 week outage for installation 8,232,000

Pre Production Costs (G) 2% of (D+E)) 475,098

Inventory Capital Reagent Vol * $/gal 2,331

Total Capital Investment (TCI) = DC + IC D + E + F + G +H + I 24,232,317 Retrofit multiplier 3 

### 60% of TCI 14,539,390 Total Retorfit Capital Investment 38,771,707



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Total 1.50 % of Total Capital Investment 363,485 Maintenance Materials NA % of Maintenance Labor - Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 1,444 kW-hr, 8339.1 hr/yr, 93% utilizati on 672,157 NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - Cat. Replacement [14] 35.00 Catalyst Replacement 423,178 NA NA - Ammonia 0.12 $/lb, 69 lb/hr, 8339.1 hr/yr, 93% utilization 64 ,238 NA NA - NA NA - NA NA - Total Annual Direct Operating Costs 1,642,933

Indirect Operating Costs Overhead 60% of total labor and material costs 40,360 Administration (2% total capital costs) 2% of total capital costs (TCI) 484,646 Property tax (1% total capital costs) 1% of total capital costs (TCI) 242,323 Insurance (1% total capital costs) 1% of total capital costs (TCI) 242,323 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 2,287,359 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 3,297,011

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,939,944

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (100) NOx SCR+ Reheat 90% Eff (100) 29 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 11: - SCR + Reheat (100)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Equivalent Duty 1,052 Plant Cap kW A 107,954 Est power platn eff 35% Unc Nox lb/mmBtu B 0.05 D=75*(300,000)*((B/1.5)^0.05*(C/100)^0.04)A)^0.35 Watt per Btu/hr 0.29307 Nox Red. Eff. C 80% E=D*A*0.0066 Equivalent power plant kW 107,954 Capital Cost $/kW D $94.41 $10,191,798.18 Total SCR Equipment Uncontrolled Nox t/y 112.4 Fixed O&M E $67,265.87 Annual Operating Hrs 8000 Variable O&M F $205,606.98 Uncontrolled Nox lb/mmBtu 0.049 Ann Cap Factor G 0.82 Heat Input mmBtu/hr

H 6,000 SCR Capital Cost

Duty 1,052 MMBtu/hr Catalyst Area 

### 508 ft 2 

### 614 f (h SCR) Q flue gas 487,426 acfm Rx Area 584 83 f (h NH 3 

### ) NOx Cont Eff 80% (as faction) Rx Height 24.2 ft 0 f (h New) new= -728, Retrofit = 0 NOx in 0.05 lb/MMBtu n layer 22 layers Y Bypass? Y or N Ammonia Slip 2 ppm h layer 23.5 ft 127 f (h Bypass) Fuel Sulfur 0.67 wt % (as %) n total 23 layers 8,220,568 f (vol catalyst) Temperature 142 Deg F h SCR 131 ft f (h SCR) Catalyst Volume 34,252 ft 3 New/Retrofit 

### R N or R

Electrical Use Duty 1,052 MMBtu/hr kW NOx Cont Eff 80% (as faction) Power 1,444.5 NOx in 0.05 lb/MMBtu n catalyst layers 23 layers Press drop catalyst 

### 1 in H 2 

### O per layer Press drop duct 

### 3 in H 2 

### O Total 1444.5

Reagent Use & Other Operating Costs Ammonia Use 56.0 lb/ft 3 

### Density

20 lb/hr Neat 9.2 gal/hr 29% solution Volume 14 day inventory 3,083 gal $2,331 In ventory Cost 69 lb/hr

Design Basis Baseline Emis. Baseline Emis.

Max Emis. (Model) Control Eff (%) Cont. Emis (lb/MMBt u) T/yr lb/MMBtu lb/hr 80% 0.01 Nitrous Oxides (NOx) 112.4 0.05 51.25

Actual 69,180 dscf/MMBtu Method 19 Factor 9,860 dscf/MMBtu Adjusted Duty 1,052 MMBtu/hr

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maintenance Total 1.5 % of Total Capital Investment 363,485 % of Total Capital Investment Maint Mtls 0 % of Maintenance Labor NA 0 0% of Maintenan ce Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 1444.5 kW-hr 11,202,612 672,157 $ /kwh, 1,444 kW-hr, 8339.1 hr/yr, 93% utilization

Cat. Replacement [14] 35 $/MW-hr 108.0 mw 112 423,178 Cata lyst Replacement

7 Ammonia 0.12 $/lb 69 lb/hr 532,660 64,238 $/lb, 69 lb/hr, 8339.1 hr/yr, 93% utilization

** Std Air use is 2 scfm/kacfm *annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 12: Reheat (100)

Operating Unit: Furnace 11 Hood Exhaust

Emission Unit Number EU 100 Stack/Vent Number SV 101, 102, & 103 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 181,762 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 142 Deg F 1998/ 1999 390 Expected Annual Hours of Operation 8,339 Hours Moistur e Content 11.3% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 172,951 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 535,530 Purchased Equipment Total (B) 22% of control device cost (A) 650,668

Installation - Standard Costs 30% of purchased equi p cost (B) 195,201 Installation - Site Specific Costs 6,200,000 Installation Total 6,395,201 Total Direct Capital Cost, DC 7,045,869 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 201,707 Total Capital Investment (TCI) = DC + IC 7,247,576

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 5,658,549 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,029,530 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 6,688,079

Notes & Assumptions 1 Equipment cost estimate EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 3.2 Chapter 2.5.1 2 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 3.2 Chapter 2

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 12: Reheat (100)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) 535,530 Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC Instrumentation 10% of control device cost (A) 53,553 MN Sales Taxes 6.5% of control device cost (A) 34,809 Freight 5% of control device cost (A) 26,776 Purchased Equipment Total (B) 22% 650,668

Installation Foundations & supports 8% of purchased equip cost (B) 52,053 Handling & erection 14% of purchased equip cost (B) 91,094 Electrical 4% of purchased equip cost (B) 26,027 Piping 2% of purchased equip cost (B) 13,013 Insulation 1% of purchased equip cost (B) 6,507 Painting 1% of purchased equip cost (B) 6,507 Installation Subtotal Standard Expenses 30% 195,201

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000 Installation Total 6,395,201 Total Direct Capital Cost, DC 7,045,869

Indirect Capital Costs Engineering, supervision 10% of purchased equip cost (B) 65,067 Construction & field expenses 5% of purchased equip cost (B) 32,533 Contractor fees 10% of purchased equip cost (B) 65,067 Start-up 2% of purchased equip cost (B) 13,013 Performance test 1% of purchased equip cost (B) 6,507 Model Studies of purchased equip cost (B) 0 Contingencies 3% of purchased equip cost (B) 19,520 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 201,707

Total Capital Investment (TCI) = DC + IC 7,247,576

Adjusted TCI for Replacement Parts (Catalyst, Filte r Bags, etc) for Capital Recovery Cost 7,247,576



### OPERATING COSTS Direct Annual Operating Costs, DC
Operating Labor Operator 50.00 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 60.00 $/Hr, 0.5 hr/8 hr shift, 833 9.1 hr/yr 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 824 kW-hr, 8339.1 hr/yr, 93% utilization 383,421 Natural Gas 10.02 $/mscf, 1,112 scfm, 8339.1 hr/yr, 93% utilizat ion 5,182,616

Total Annual Direct Operating Costs 5,658,549

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 144,952 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 72,476 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 72,476 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 684,120 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,029,530

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 6,688,079

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: United Taconite BART Report - <Insert attachment name> Emission Con trol Cost Analysis Table 12: Reheat (100)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Catalyst Equipment Life 2 years CRF 0.5531 Rep part cost per unit 0 $/ft 3 Amount Required 39 ft 3 Catalyst Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst c ost (basis labor for baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQPS list replacement times from 5 - 20 min per ba g. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm **∆** P in H2O Efficiency Hp kW Blower, Thermal 222,400 19 0.6 824.0 EPA Cost Cont Manua l 6th ed - Oxidizders Chapter 2.5.2.1 Blower, Catalytic 222,400 23 0.6 997.5 EPA Cost Cont Man ual 6th ed - Oxidizders Chapter 2.5.2.1

Oxidizer Type thermal (catalytic or thermal) 824.0

Reagent Use & Other Operating Costs Oxidizers - NA

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 824.0 kW-hr 6,390,357 383,421 $/k wh, 824 kW-hr, 8339.1 hr/yr, 93% utilization Natural Gas 10.02 $/mscf 1,112 scfm 517,206 5,182,616 $/m scf, 1,112 scfm, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 12: Reheat (100)

Flue Gas Re-Heat Equipment Cost Estimate Basis The rmal Oxidizer with 70% Heat Recovery

Auxiliary Fuel Use Equation 3.19 T wi 142 Deg F - Temperature of waste gas into heat rec overy T fi 750 Deg F - Temperature of Flue gas into of heat r ecovery T ref 77 Deg F - Reference temperature for fuel combustio n calculations FER 70% Factional Heat Recovery % Heat recovery sect ion efficiency

T wo 568 Deg F - Temperature of waste gas out of heat r ecovery

T fo 324 Deg F - Temperature of flue gas into of heat r ecovery

-h caf 21502 Btu/lb Heat of combustion auxiliary fuel (met hane)
-h wg 0 Btu/lb Heat of combustion waste gas C p wg 0.2684 Btu/lb - Deg F Heat Capacity of waste gas (a ir) p wg 0.0739 lb/scf - Density of waste gas (air) at 77 De g F p af 0.0408 lb/scf - Density of auxiliary fuel (methane) at 77 Deg F Q wg 195,062 scfm - Flow of waste gas

Q af 1,112 scfm - Flow of auxiliary fuel

Year 2005 Inflation Rate 3.0% Cost Calculations 196,173 scfm Flue Gas Cost in 1989 $'s $449,154 Current Cost Using CHE Plant Cost Index $535,530 Heat Rec % A B

0 10,294 0.2355 Exponents per equation 3.24 0.3 13,149 0.2609 Exponents per equation 3.25 0.5 17,056 0.2502 Exponents per equation 3.26 0.7 21,342 0.2500 Exponents per equation 3.27

Indurator Flue Gas Heat Capacity - Basis Typical Co mposition

100 scfm 359 scf/lbmole Gas Composition lb/hr f wt % Cp Gas Cp Flue 28 mw CO 0 v % 0 44 mw CO2 15 v % 184 22.0% 0.24 0.0528 18 mw H2O 10 v % 50 6.0% 0.46 0.0276 28 mw N2 60 v % 468 56.0% 0.27 0.1512 32 mw O2 15 v % 134 16.0% 0.23 0.0368 Cp Flue Gas 100 v % 836 100.0% 0.2684

Reference: OAQPS Control Cost Manual 5th Ed Feb 1996 - Chapter 3 Thermal & Catalytic Incinerators (EPA 453/B-96-001)

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 13: - SCR + Reheat (104)

Operating Unit: Furnace 11 Waste Gas

Emission Unit Number EU 104 Stack/Vent Number SV 104 & 105 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 152,520 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 140 Deg F 1998/1999 390 Expected Annual Hours of Operation 8,339 Hours Moisture Content 18.3% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 163,680 scfm @ 68o F Dry Std Flow Rate 133,792 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Year Direct Capital Costs EPRI Correlation 1998 Purchased Equipment (A) 2005 0 Purchased Equipment Total (B) 0% of control device cost (A) SCR Only 9,372,318

Installation - Standard Costs 15% of purchased equi p cost (B) SCR Only 1,802,433 Installation - Site Specific Costs 0 Installation Total 0 Total Direct Capital Cost, DC 0 Total Indirect Capital Costs, IC 0% of purchased equip cost (B) 0 Total Capital Investment (TCI) = DC + IC SCR + Reheat 43,197,692

Operating Costs Total Annual Direct Operating Costs Labor, supervision, materials, replacement parts, u tilities, etc. SCR + Reheat 4,157,530 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost SCR + Reheat 4,081,731 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) SCR + Reheat 8,239,261



### Emission Control Cost Calculation Baseline Predicted Limit Cont. Emis. Cont Emis Reduct ion Cont Cost Pollutant Emis. T/yr lb/hr lb/MMBtu T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 273.7 4.6

0.03

17.8 255.9 32,199

Notes & Assumptions 1 Estimated Equipment Cost per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2. 2 For Calculation purposes, duty reflects increased f low rate, not actual duty. 3 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 4 Capital Cost per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.36 -2.4 3 5 Reagent Use per EPA Air Pollution Control Cost Manu al 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.32 - 2.3 5 6 SCR Catalyst Volume per EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2. 18 - 2.24 7 SCR Reactor Size per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.25 - 2.31 8 SCR Catalyst Replacement per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.50 - 2.53 9 SCR Electrical Demand per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.48 10 SCR Maintenance Costs EPA Air Pollution Control Cos t Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.46 11 Control Efficiency = 90% reduction which is typical ly the upper range of normal SCR control efficiency 12 $35/MW-hr, 140 MW 13 Catalyst replacement every 8000 hours. This requir es an additional 2 week outage per 3 year outage cy cle, annualized to 4.7 days.

Notes to User

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 13: - SCR + Reheat (104)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC 8,800,299 Instrumentation 10% of control device cost (A) NA MN Sales Taxes 6.5% of control device cost (A) 572,019 Freight 5% of control device cost (A) NA Purchased Equipment Total (A) 9,372,318

Indirect Installation General Facilities 0% of purchased equip cost (A) 0 Engineering & Home Office 0% of purchased equip cost (A) 0 Process Contingency 0% of purchased equip cost (A) 0 Site Specific-Other 28% Replacement Power, two weeks 2,643,899

Total Indirect Installation Costs (B) 28% of purchased equip cost (A) 2,643,899

Project Contingeny ( C) 15% of (A + B) 1,802,433

Total Plant Cost D A + B + C 13,818,649

Allowance for Funds During Construction (E) Additional 10 week outage for installation 8,232,000

Pre Production Costs (G) 2% of (D+E)) 441,013

Inventory Capital Reagent Vol * $/gal 5,677

Total Capital Investment (TCI) = DC + IC D + E + F + G +H + I 22,497,340 Retrofit multiplier 3 

### 60% of TCI 13,498,404 Total Retorfit Capital Investment 35,995,743



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Total 1.50 % of Total Capital Investment 337,460 Maintenance Materials NA % of Maintenance Labor - Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 1,167 kW-hr, 8339.1 hr/yr, 93% utilizati on 543,246 NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - Cat. Replacement [14] 35.00 Catalyst Replacement 327,363 NA NA - Ammonia 0.12 $/lb, 167 lb/hr, 8339.1 hr/yr, 93% utilization 1 56,470 NA NA - NA NA - NA NA - Total Annual Direct Operating Costs 1,484,414

Indirect Operating Costs Overhead 60% of total labor and material costs 34,849 Administration (2% total capital costs) 2% of total capital costs (TCI) 449,947 Property tax (1% total capital costs) 1% of total capital costs (TCI) 224,973 Insurance (1% total capital costs) 1% of total capital costs (TCI) 224,973 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 2,123,590 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 3,058,332

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,542,746

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 13: - SCR + Reheat (104)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Equivalent Duty 814 Plant Cap kW A 83,511 Est power platn eff 35% Unc Nox lb/mmBtu B 0.15 D=75*(300,000)*((B/1.5)^0.05*(C/100)^0.04)A)^0.35 Watt per Btu/hr 0.29307 Nox Red. Eff. C 80% E=D*A*0.0066 Equivalent power plant kW 83,511 Capital Cost $/kW D $105.38 $8,800,298.76 Total SCR Equipment Uncontrolled Nox t/y 273.7 Fixed O&M E $58,081.97 Annual Operating Hrs 8000 Variable O&M F $171,504.18 Uncontrolled Nox lb/mmBtu 0.153 Ann Cap Factor G 0.82 Heat Input mmBtu/hr

H 6,000 SCR Capital Cost

Duty 814 MMBtu/hr Catalyst Area 

### 393 ft 2 

### 638 f (h SCR) Q flue gas 377,064 acfm Rx Area 452 121 f (h NH 3 

### ) NOx Cont Eff 80% (as faction) Rx Height 21.3 ft 0 f (h New) new= -728, Retrofit = 0 NOx in 0.15 lb/MMBtu n layer 23 layers Y Bypass? Y or N Ammonia Slip 2 ppm h layer 24.5 ft 127 f (h Bypass) Fuel Sulfur 0.67 wt % (as %) n total 24 layers 6,646,500 f (vol catalyst) Temperature 140 Deg F h SCR 135 ft f (h SCR) Catalyst Volume 27,694 ft 3 New/Retrofit 

### R N or R

Electrical Use Duty 814 MMBtu/hr kW NOx Cont Eff 80% (as faction) Power 1,167.5 NOx in 0.15 lb/MMBtu n catalyst layers 24 layers Press drop catalyst 

### 1 in H 2 

### O per layer Press drop duct 

### 3 in H 2 

### O Total 1167.5

Reagent Use & Other Operating Costs Ammonia Use 56.0 lb/ft 3 

### Density

49 lb/hr Neat 22.3 gal/hr 29% solution Volume 14 day inventory 7,509 gal $5,677 In ventory Cost 167 lb/hr

Design Basis Baseline Emis. Baseline Emis.

Max Emis. (Model) Control Eff (%) Cont. Emis (lb/MMBt u) T/yr lb/MMBtu lb/hr 80% 0.03 Nitrous Oxides (NOx) 273.7 0.15 124.83

Actual 53,517 dscf/MMBtu Method 19 Factor 9,860 dscf/MMBtu Adjusted Duty 814 MMBtu/hr

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maintenance Total 1.5 % of Total Capital Investment 337,460 % of Total Capital Investment Maint Mtls 0 % of Maintenance Labor NA 0 0% of Maintenan ce Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 1167.5 kW-hr 9,054,097 543,246 $/ kwh, 1,167 kW-hr, 8339.1 hr/yr, 93% utilization

Cat. Replacement [14] 35 $/MW-hr 83.5 mw 112 327,363 Catal yst Replacement

7 Ammonia 0.12 $/lb 167 lb/hr 1,297,437 156,470 $/lb, 167 lb/hr, 8339.1 hr/yr, 93% utilization

** Std Air use is 2 scfm/kacfm *annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 14: - Reheat (104)

Operating Unit: Furnace 11 Waste Gas

Emission Unit Number EU 104 Stack/Vent Number SV 104 & 105 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 152,520 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 140 Deg F 1998/ 1999 390 Expected Annual Hours of Operation 8,339 Hours Moistur e Content 18.3% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 133,792 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 512,205 Purchased Equipment Total (B) 22% of control device cost (A) 622,328

Installation - Standard Costs 30% of purchased equi p cost (B) 186,699 Installation - Site Specific Costs 6,200,000 Installation Total 6,386,699 Total Direct Capital Cost, DC 7,009,027 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 192,922 Total Capital Investment (TCI) = DC + IC 7,201,949

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 2,673,116 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,023,398 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,696,515

Notes & Assumptions 1 Equipment cost estimate EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 3.2 Chapter 2.5.1 2 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 3.2 Chapter 2

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 14: - Reheat (104)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) 512,205 Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC Instrumentation 10% of control device cost (A) 51,220 MN Sales Taxes 6.5% of control device cost (A) 33,293 Freight 5% of control device cost (A) 25,610 Purchased Equipment Total (B) 22% 622,328

Installation Foundations & supports 8% of purchased equip cost (B) 49,786 Handling & erection 14% of purchased equip cost (B) 87,126 Electrical 4% of purchased equip cost (B) 24,893 Piping 2% of purchased equip cost (B) 12,447 Insulation 1% of purchased equip cost (B) 6,223 Painting 1% of purchased equip cost (B) 6,223 Installation Subtotal Standard Expenses 30% 186,699

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000 Installation Total 6,386,699 Total Direct Capital Cost, DC 7,009,027

Indirect Capital Costs Engineering, supervision 10% of purchased equip cost (B) 62,233 Construction & field expenses 5% of purchased equip cost (B) 31,116 Contractor fees 10% of purchased equip cost (B) 62,233 Start-up 2% of purchased equip cost (B) 12,447 Performance test 1% of purchased equip cost (B) 6,223 Model Studies of purchased equip cost (B) 0 Contingencies 3% of purchased equip cost (B) 18,670 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 192,922

Total Capital Investment (TCI) = DC + IC 7,201,949

Adjusted TCI for Replacement Parts (Catalyst, Filte r Bags, etc) for Capital Recovery Cost 7,201,949



### OPERATING COSTS Direct Annual Operating Costs, DC
Operating Labor Operator 50.00 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 60.00 $/Hr, 0.5 hr/8 hr shift, 833 9.1 hr/yr 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 689 kW-hr, 8339.1 hr/yr, 93% utilization 320,667 Natural Gas 10.02 $/mscf, 485 scfm, 8339.1 hr/yr, 93% utilizatio n 2,259,937

Total Annual Direct Operating Costs 2,673,116

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 144,039 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 72,019 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 72,019 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 679,813 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,023,398

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 3,696,515

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: United Taconite BART Report - <Insert attachment name> Emission Con trol Cost Analysis Table 14: - Reheat (104)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Catalyst Equipment Life 2 years CRF 0.5531 Rep part cost per unit 0 $/ft 3 Amount Required 39 ft 3 Catalyst Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst c ost (basis labor for baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQPS list replacement times from 5 - 20 min per ba g. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm **∆** P in H2O Efficiency Hp kW Blower, Thermal 186,000 19 0.6 689.1 EPA Cost Cont Manua l 6th ed - Oxidizders Chapter 2.5.2.1 Blower, Catalytic 186,000 23 0.6 834.2 EPA Cost Cont Man ual 6th ed - Oxidizders Chapter 2.5.2.1

Oxidizer Type thermal (catalytic or thermal) 689.1

Reagent Use & Other Operating Costs Oxidizers - NA

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 689.1 kW-hr 5,344,453 320,667 $/k wh, 689 kW-hr, 8339.1 hr/yr, 93% utilization Natural Gas 10.02 $/mscf 485 scfm 225,534 2,259,937 $/msc f, 485 scfm, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 14: - Reheat (104)

Flue Gas Re-Heat Equipment Cost Estimate Basis The rmal Oxidizer with 70% Heat Recovery

Auxiliary Fuel Use Equation 3.19 T wi 140 Deg F - Temperature of waste gas into heat rec overy T fi 450 Deg F - Temperature of Flue gas into of heat r ecovery T ref 77 Deg F - Reference temperature for fuel combustio n calculations FER 70% Factional Heat Recovery % Heat recovery sect ion efficiency

T wo 357 Deg F - Temperature of waste gas out of heat r ecovery

T fo 233 Deg F - Temperature of flue gas into of heat r ecovery

-h caf 21502 Btu/lb Heat of combustion auxiliary fuel (met hane)
-h wg 0 Btu/lb Heat of combustion waste gas C p wg 0.2684 Btu/lb - Deg F Heat Capacity of waste gas (a ir) p wg 0.0739 lb/scf - Density of waste gas (air) at 77 De g F p af 0.0408 lb/scf - Density of auxiliary fuel (methane) at 77 Deg F Q wg 163,680 scfm - Flow of waste gas

Q af 485 scfm - Flow of auxiliary fuel

Year 2005 Inflation Rate 3.0% Cost Calculations 164,165 scfm Flue Gas Cost in 1989 $'s $429,591 Current Cost Using CHE Plant Cost Index $512,205 Heat Rec % A B

0 10,294 0.2355 Exponents per equation 3.24 0.3 13,149 0.2609 Exponents per equation 3.25 0.5 17,056 0.2502 Exponents per equation 3.26 0.7 21,342 0.2500 Exponents per equation 3.27

Indurator Flue Gas Heat Capacity - Basis Typical Co mposition

100 scfm 359 scf/lbmole Gas Composition lb/hr f wt % Cp Gas Cp Flue 28 mw CO 0 v % 0 44 mw CO2 15 v % 184 22.0% 0.24 0.0528 18 mw H2O 10 v % 50 6.0% 0.46 0.0276 28 mw N2 60 v % 468 56.0% 0.27 0.1512 32 mw O2 15 v % 134 16.0% 0.23 0.0368 Cp Flue Gas 100 v % 836 100.0% 0.2684

Reference: OAQPS Control Cost Manual 5th Ed Feb 1996 - Chapter 3 Thermal & Catalytic Incinerators (EPA 453/B-96-001)

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 15: - SCR + Reheat (110)

Operating Unit: Furnace 12 Hood Exhaust

Emission Unit Number EU 110 Stack/Vent Number SV 111, 112, & 113 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 181,762 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 142 Deg F 1998/1999 390 Expected Annual Hours of Operation 8,339 Hours Moisture Content 9.5% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 195,062 scfm @ 68o F Dry Std Flow Rate 176,529 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Year Direct Capital Costs EPRI Correlation 1998 Purchased Equipment (A) 2005 10,324,640 Purchased Equipment Total (B) 0% of control device cost (A) SCR Only 10,995,741

Installation - Standard Costs 15% of purchased equi p cost (B) SCR Only 2,045,946 Installation - Site Specific Costs 0 Installation Total 0 Total Direct Capital Cost, DC 0 Total Indirect Capital Costs, IC 0% of purchased equip cost (B) 0 Total Capital Investment (TCI) = DC + IC SCR + Reheat 46,284,809

Operating Costs Total Annual Direct Operating Costs Labor, supervision, materials, replacement parts, u tilities, etc. SCR + Reheat 7,339,040 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost SCR + Reheat 4,349,371 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) SCR + Reheat 11,688,411



### Emission Control Cost Calculation Baseline Predicted Limit Cont. Emis. Cont Emis Reduct ion Cont Cost Pollutant Emis. T/yr lb/hr lb/MMBtu T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 109.9 1.4

0.01

5.6 104.4 112,008

Notes & Assumptions 1 Estimated Equipment Cost per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2. 2 For Calculation purposes, duty reflects increased f low rate, not actual duty. 3 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 4 Capital Cost per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.36 -2.4 3 5 Reagent Use per EPA Air Pollution Control Cost Manu al 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.32 - 2.3 5 6 SCR Catalyst Volume per EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2. 18 - 2.24 7 SCR Reactor Size per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.25 - 2.31 8 SCR Catalyst Replacement per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.50 - 2.53 9 SCR Electrical Demand per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.48 10 SCR Maintenance Costs EPA Air Pollution Control Cos t Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.46 11 Control Efficiency = 90% reduction which is typical ly the upper range of normal SCR control efficiency 12 $35/MW-hr, 140 MW 13 Catalyst replacement every 8000 hours. This requir es an additional 2 week outage per 3 year outage cy cle, annualized to 4.7 days.

Notes to User

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (110) NOx SCR+ Reheat 90% Eff (110) 42 of 56

## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 15: - SCR + Reheat (110)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC 10,324,640 Instrumentation 10% of control device cost (A) NA MN Sales Taxes 6.5% of control device cost (A) 671,102 Freight 5% of control device cost (A) NA Purchased Equipment Total (A) 10,995,741

Indirect Installation General Facilities 0% of purchased equip cost (A) 0 Engineering & Home Office 0% of purchased equip cost (A) 0 Process Contingency 0% of purchased equip cost (A) 0 Site Specific-Other 24% Replacement Power, two weeks 2,643,899

Total Indirect Installation Costs (B) 24% of purchased equip cost (A) 2,643,899

Project Contingeny ( C) 15% of (A + B) 2,045,946

Total Plant Cost D A + B + C 15,685,586

Allowance for Funds During Construction (E) Additional 10 week outage for installation 8,232,000

Pre Production Costs (G) 2% of (D+E)) 478,352

Inventory Capital Reagent Vol * $/gal 2,331

Total Capital Investment (TCI) = DC + IC D + E + F + G +H + I 24,398,268 Retrofit multiplier 3 

### 60% of TCI 14,638,961 Total Retorfit Capital Investment 39,037,230



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Total 1.50 % of Total Capital Investment 365,974 Maintenance Materials NA % of Maintenance Labor - Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 1,474 kW-hr, 8339.1 hr/yr, 93% utilizati on 686,019 NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - Cat. Replacement [14] 35.00 Catalyst Replacement 431,932 NA NA - Ammonia 0.12 $/lb, 69 lb/hr, 8339.1 hr/yr, 93% utilization 64 ,238 NA NA - NA NA - NA NA - Total Annual Direct Operating Costs 1,668,038

Indirect Operating Costs Overhead 60% of total labor and material costs 40,886 Administration (2% total capital costs) 2% of total capital costs (TCI) 487,965 Property tax (1% total capital costs) 1% of total capital costs (TCI) 243,983 Insurance (1% total capital costs) 1% of total capital costs (TCI) 243,983 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 2,303,024 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 3,319,840

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,987,878

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (110) NOx SCR+ Reheat 90% Eff (110) 43 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 15: - SCR + Reheat (110)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Equivalent Duty 1,074 Plant Cap kW A 110,187 Est power platn eff 35% Unc Nox lb/mmBtu B 0.05 D=75*(300,000)*((B/1.5)^0.05*(C/100)^0.04)A)^0.35 Watt per Btu/hr 0.29307 Nox Red. Eff. C 80% E=D*A*0.0066 Equivalent power plant kW 110,187 Capital Cost $/kW D $93.70 $10,324,639.77 Total SCR Equipment Uncontrolled Nox t/y 109.9 Fixed O&M E $68,142.62 Annual Operating Hrs 8000 Variable O&M F $209,166.23 Uncontrolled Nox lb/mmBtu 0.048 Ann Cap Factor G 0.82 Heat Input mmBtu/hr

H 6,000 SCR Capital Cost

Duty 1,074 MMBtu/hr Catalyst Area 

### 518 ft 2 

### 613 f (h SCR) Q flue gas 497,508 acfm Rx Area 596 80 f (h NH 3 

### ) NOx Cont Eff 80% (as faction) Rx Height 24.4 ft 0 f (h New) new= -728, Retrofit = 0 NOx in 0.05 lb/MMBtu n layer 22 layers Y Bypass? Y or N Ammonia Slip 2 ppm h layer 23.5 ft 127 f (h Bypass) Fuel Sulfur 0.67 wt % (as %) n total 23 layers 8,387,553 f (vol catalyst) Temperature 142 Deg F h SCR 131 ft f (h SCR) Catalyst Volume 34,948 ft 3 New/Retrofit 

### R N or R

Electrical Use Duty 1,074 MMBtu/hr kW NOx Cont Eff 80% (as faction) Power 1,474.3 NOx in 0.05 lb/MMBtu n catalyst layers 23 layers Press drop catalyst 

### 1 in H 2 

### O per layer Press drop duct 

### 3 in H 2 

### O Total 1474.3

Reagent Use & Other Operating Costs Ammonia Use 56.0 lb/ft 3 

### Density

20 lb/hr Neat 9.2 gal/hr 29% solution Volume 14 day inventory 3,083 gal $2,331 In ventory Cost 69 lb/hr

Design Basis Baseline Emis. Baseline Emis.

Max Emis. (Model) Control Eff (%) Cont. Emis (lb/MMBt u) T/yr lb/MMBtu lb/hr 80% 0.01 Nitrous Oxides (NOx) 109.9 0.05 51.25

Actual 70,611 dscf/MMBtu Method 19 Factor 9,860 dscf/MMBtu Adjusted Duty 1,074 MMBtu/hr

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maintenance Total 1.5 % of Total Capital Investment 365,974 % of Total Capital Investment Maint Mtls 0 % of Maintenance Labor NA 0 0% of Maintenan ce Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 1474.3 kW-hr 11,433,649 686,019 $ /kwh, 1,474 kW-hr, 8339.1 hr/yr, 93% utilization

Cat. Replacement [14] 35 $/MW-hr 110.2 mw 112 431,932 Cata lyst Replacement

7 Ammonia 0.12 $/lb 69 lb/hr 532,660 64,238 $/lb, 69 lb/hr, 8339.1 hr/yr, 93% utilization

** Std Air use is 2 scfm/kacfm *annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (110) NOx SCR+ Reheat 90% Eff (110) 44 of 56

## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 16: - Reheat (110)

Operating Unit: Furnace 12 Hood Exhaust

Emission Unit Number EU 110 Stack/Vent Number SV 111, 112, & 113 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 181,762 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 142 Deg F 1998/ 1999 390 Expected Annual Hours of Operation 8,339 Hours Moistur e Content 9.5% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 222,400 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 1 95,062 scfm @ 68o F Dry Std Flow Rate 176,529 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 535,531 Purchased Equipment Total (B) 22% of control device cost (A) 650,671

Installation - Standard Costs 30% of purchased equi p cost (B) 195,201 Installation - Site Specific Costs 6,200,000 Installation Total 6,395,201 Total Direct Capital Cost, DC 7,045,872 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 201,708 Total Capital Investment (TCI) = DC + IC 7,247,580

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 5,671,002 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,029,531 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 6,700,533

Notes & Assumptions 1 Equipment cost estimate EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 3.2 Chapter 2.5.1 2 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 3.2 Chapter 2

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 16: - Reheat (110)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) 535,531 Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC Instrumentation 10% of control device cost (A) 53,553 MN Sales Taxes 6.5% of control device cost (A) 34,810 Freight 5% of control device cost (A) 26,777 Purchased Equipment Total (B) 22% 650,671

Installation Foundations & supports 8% of purchased equip cost (B) 52,054 Handling & erection 14% of purchased equip cost (B) 91,094 Electrical 4% of purchased equip cost (B) 26,027 Piping 2% of purchased equip cost (B) 13,013 Insulation 1% of purchased equip cost (B) 6,507 Painting 1% of purchased equip cost (B) 6,507 Installation Subtotal Standard Expenses 30% 195,201

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000 Installation Total 6,395,201 Total Direct Capital Cost, DC 7,045,872

Indirect Capital Costs Engineering, supervision 10% of purchased equip cost (B) 65,067 Construction & field expenses 5% of purchased equip cost (B) 32,534 Contractor fees 10% of purchased equip cost (B) 65,067 Start-up 2% of purchased equip cost (B) 13,013 Performance test 1% of purchased equip cost (B) 6,507 Model Studies of purchased equip cost (B) 0 Contingencies 3% of purchased equip cost (B) 19,520 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 201,708

Total Capital Investment (TCI) = DC + IC 7,247,580

Adjusted TCI for Replacement Parts (Catalyst, Filte r Bags, etc) for Capital Recovery Cost 7,247,580



### OPERATING COSTS Direct Annual Operating Costs, DC
Operating Labor Operator 50.00 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 60.00 $/Hr, 0.5 hr/8 hr shift, 833 9.1 hr/yr 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 824 kW-hr, 8339.1 hr/yr, 93% utilization 383,421 Natural Gas 10.02 $/mscf, 1,114 scfm, 8339.1 hr/yr, 93% utilizat ion 5,195,069

Total Annual Direct Operating Costs 5,671,002

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 144,952 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 72,476 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 72,476 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 684,120 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,029,531

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 6,700,533

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: United Taconite BART Report - <Insert attachment name> Emission Con trol Cost Analysis Table 16: - Reheat (110)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Catalyst Equipment Life 2 years CRF 0.5531 Rep part cost per unit 0 $/ft 3 Amount Required 39 ft 3 Catalyst Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst c ost (basis labor for baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sa les tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQPS list replacement times from 5 - 20 min per ba g. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm **∆** P in H2O Efficiency Hp kW Blower, Thermal 222,400 19 0.6 824.0 EPA Cost Cont Manua l 6th ed - Oxidizders Chapter 2.5.2.1 Blower, Catalytic 222,400 23 0.6 997.5 EPA Cost Cont Man ual 6th ed - Oxidizders Chapter 2.5.2.1

Oxidizer Type thermal (catalytic or thermal) 824.0

Reagent Use & Other Operating Costs Oxidizers - NA

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 824.0 kW-hr 6,390,357 383,421 $/k wh, 824 kW-hr, 8339.1 hr/yr, 93% utilization Natural Gas 10.02 $/mscf 1,114 scfm 518,449 5,195,069 $/m scf, 1,114 scfm, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 16: - Reheat (110)

Flue Gas Re-Heat Equipment Cost Estimate Basis The rmal Oxidizer with 70% Heat Recovery

Auxiliary Fuel Use Equation 3.19 T wi 140 Deg F - Temperature of waste gas into heat rec overy T fi 750 Deg F - Temperature of Flue gas into of heat r ecovery T ref 77 Deg F - Reference temperature for fuel combustio n calculations FER 70% Factional Heat Recovery % Heat recovery sect ion efficiency

T wo 567 Deg F - Temperature of waste gas out of heat r ecovery

T fo 323 Deg F - Temperature of flue gas into of heat r ecovery

-h caf 21502 Btu/lb Heat of combustion auxiliary fuel (met hane)
-h wg 0 Btu/lb Heat of combustion waste gas C p wg 0.2684 Btu/lb - Deg F Heat Capacity of waste gas (a ir) p wg 0.0739 lb/scf - Density of waste gas (air) at 77 De g F p af 0.0408 lb/scf - Density of auxiliary fuel (methane) at 77 Deg F Q wg 195,062 scfm - Flow of waste gas

Q af 1,114 scfm - Flow of auxiliary fuel

Year 2005 Inflation Rate 3.0% Cost Calculations 196,176 scfm Flue Gas Cost in 1989 $'s $449,155 Current Cost Using CHE Plant Cost Index $535,531 Heat Rec % A B

0 10,294 0.2355 Exponents per equation 3.24 0.3 13,149 0.2609 Exponents per equation 3.25 0.5 17,056 0.2502 Exponents per equation 3.26 0.7 21,342 0.2500 Exponents per equation 3.27

Indurator Flue Gas Heat Capacity - Basis Typical Co mposition

100 scfm 359 scf/lbmole Gas Composition lb/hr f wt % Cp Gas Cp Flue 28 mw CO 0 v % 0 44 mw CO2 15 v % 184 22.0% 0.24 0.0528 18 mw H2O 10 v % 50 6.0% 0.46 0.0276 28 mw N2 60 v % 468 56.0% 0.27 0.1512 32 mw O2 15 v % 134 16.0% 0.23 0.0368 Cp Flue Gas 100 v % 836 100.0% 0.2684

Reference: OAQPS Control Cost Manual 5th Ed Feb 1996 - Chapter 3 Thermal & Catalytic Incinerators (EPA 453/B-96-001)

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## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 17: - SCR + Reheat (114)

Operating Unit: Furnace 12 Waste Gas

Emission Unit Number EU 114 Stack/Vent Number SV 114 & 115 Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 152,520 scfm @ 32o F Expected Utiliztion Rate 93% Temperature 140 Deg F Expected Annual Hours of Operation 8,339 Hours Moisture Content 16.4% Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Expected Equipment Life 20 yrs Standardized Flow Rate 163,680 scfm @ 68o F Dry Std Flow Rate 136,902 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs EPRI Correlation Purchased Equipment (A) 8,929,135 Purchased Equipment Total (B) SCR Only 9,509,529

Installation - Standard Costs 15% of purchased equi p cost (B) SCR Only 1,823,014 Installation - Site Specific Costs 0 Installation Total 0 Total Direct Capital Cost, DC 0 Total Indirect Capital Costs, IC 0% of purchased equip cost (B) 0 Total Capital Investment (TCI) = DC + IC SCR + Reheat 43,455,895

Operating Costs Total Annual Direct Operating Costs Labor, supervision, materials, replacement parts, u tilities, etc. SCR + Reheat 6,279,410 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost SCR + Reheat 4,103,963 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) SCR + Reheat 10,383,373



### Emission Control Cost Calculation Baseline Predicted Limit Cont. Emis. Cont Emis Reduct ion Cont Cost Pollutant Emis. T/yr lb/hr lb/MMBtu T/yr T/yr $/Ton Rem Nitrous Oxides (NOx) 267.7 4.5

0.03

17.4 250.3 41,488

Notes & Assumptions 1 Estimated Equipment Cost per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2. 2 For Calculation purposes, duty reflects increased f low rate, not actual duty. 3 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 4 Capital Cost per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.36 -2.4 3 5 Reagent Use per EPA Air Pollution Control Cost Manu al 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.32 - 2.3 5 6 SCR Catalyst Volume per EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2. 18 - 2.24 7 SCR Reactor Size per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.25 - 2.31 8 SCR Catalyst Replacement per EPA Air Pollution Cont rol Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.50 - 2.53 9 SCR Electrical Demand per EPA Air Pollution Control Cost Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.48 10 SCR Maintenance Costs EPA Air Pollution Control Cos t Manual 6th Ed 2002, Section 4.2 Chapter 2 Eq 2.46 11 Control Efficiency = 90% reduction which is typical ly the upper range of normal SCR control efficiency 12 $35/MW-hr, 140 MW 13 Catalyst replacement every 8000 hours. This requir es an additional 2 week outage per 3 year outage cy cle, annualized to 4.7 days.

Notes to User

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (114) NOx SCR+ Reheat 90% Eff (114) 49 of 56

## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 17: - SCR + Reheat (114)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC 8,929,135 Instrumentation 10% of control device cost (A) NA MN Sales Taxes 6.5% of control device cost (A) 580,394 Freight 5% of control device cost (A) NA Purchased Equipment Total (A) 9,509,529

Indirect Installation General Facilities 0% of purchased equip cost (A) 0 Engineering & Home Office 0% of purchased equip cost (A) 0 Process Contingency 0% of purchased equip cost (A) 0 Site Specific-Other 28% Replacement Power, two weeks 2,643,899

Total Indirect Installation Costs (B) 28% of purchased equip cost (A) 2,643,899

Project Contingeny ( C) 15% of (A + B) 1,823,014

Total Plant Cost D A + B + C 13,976,441

Allowance for Funds During Construction (E) Additional 10 week outage for installation 8,232,000

Pre Production Costs (G) 2% of (D+E)) 444,169

Inventory Capital Reagent Vol * $/gal 5,677

Total Capital Investment (TCI) = DC + IC D + E + F + G +H + I 22,658,287 Retrofit multiplier 3 

### 60% of TCI 13,594,972 Total Retorfit Capital Investment 36,253,260



### OPERATING COSTS Direct Annual Operating Costs, DC

Operating Labor Operator 50.00 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr 104,239 Supervisor 15% 15% of Operator Costs 15,636 Maintenance Maintenance Total 1.50 % of Total Capital Investment 339,874 Maintenance Materials NA % of Maintenance Labor - Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 1,194 kW-hr, 8339.1 hr/yr, 93% utilizati on 555,760 NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - NA NA - Cat. Replacement [14] 35.00 Catalyst Replacement 334,973 NA NA - Ammonia 0.12 $/lb, 167 lb/hr, 8339.1 hr/yr, 93% utilization 1 56,470 NA NA - NA NA - NA NA - Total Annual Direct Operating Costs 1,506,951

Indirect Operating Costs Overhead 60% of total labor and material costs 35,359 Administration (2% total capital costs) 2% of total capital costs (TCI) 453,166 Property tax (1% total capital costs) 1% of total capital costs (TCI) 226,583 Insurance (1% total capital costs) 1% of total capital costs (TCI) 226,583 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 2,138,782 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 3,080,473

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 4,587,424

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls NOx SCR+ Reheat 90% Eff (114) NOx SCR+ Reheat 90% Eff (114) 50 of 56

## Cleveland Cliffs Incorporated: Northshore Mining

BART Report - Appendix A Emission Control Cost Anal ysis Table 17: - SCR + Reheat (114)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Equivalent Duty 833 Plant Cap kW A 85,452 Est power platn eff 35% Unc Nox lb/mmBtu B 0.15 D=75*(300,000)*((B/1.5)^0.05*(C/100)^0.04)A)^0.35 Watt per Btu/hr 0.29307 Nox Red. Eff. C 80% E=D*A*0.0066 Equivalent power plant kW 85,452 Capital Cost $/kW D $104.49 $8,929,134.83 Total SCR Equipment Uncontrolled Nox t/y 267.7 Fixed O&M E $58,932.29 Annual Operating Hrs 8000 Variable O&M F $174,705.21 Uncontrolled Nox lb/mmBtu 0.150 Ann Cap Factor G 0.82 Heat Input mmBtu/hr

H 6,000 SCR Capital Cost

Duty 833 MMBtu/hr Catalyst Area 

### 402 ft 2 

### 638 f (h SCR) Q flue gas 385,829 acfm Rx Area 462 117 f (h NH 3 

### ) NOx Cont Eff 80% (as faction) Rx Height 21.5 ft 0 f (h New) new= -728, Retrofit = 0 NOx in 0.15 lb/MMBtu n layer 23 layers Y Bypass? Y or N Ammonia Slip 2 ppm h layer 24.5 ft 127 f (h Bypass) Fuel Sulfur 0.67 wt % (as %) n total 24 layers 6,792,565 f (vol catalyst) Temperature 140 Deg F h SCR 135 ft f (h SCR) Catalyst Volume 28,302 ft 3 New/Retrofit 

### R N or R

Electrical Use Duty 833 MMBtu/hr kW NOx Cont Eff 80% (as faction) Power 1,194.4 NOx in 0.15 lb/MMBtu n catalyst layers 24 layers Press drop catalyst 

### 1 in H 2 

### O per layer Press drop duct 

### 3 in H 2 

### O Total 1194.4

Reagent Use & Other Operating Costs Ammonia Use 56.0 lb/ft 3 

### Density

49 lb/hr Neat 22.3 gal/hr 29% solution Volume 14 day inventory 7,509 gal $5,677 In ventory Cost 167 lb/hr

Design Basis Baseline Emis. Baseline Emis.

Max Emis. (Model) Control Eff (%) Cont. Emis (lb/MMBt u) T/yr lb/MMBtu lb/hr 80% 0.03 Nitrous Oxides (NOx) 267.7 0.15 124.83

Actual 54,761 dscf/MMBtu Method 19 Factor 9,860 dscf/MMBtu Adjusted Duty 833 MMBtu/hr

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 2.0 hr/8 hr shift 2,085 104,239 $/Hr, 2.0 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 15,636 15% of Operator Costs Maintenance Maintenance Total 1.5 % of Total Capital Investment 339,874 % of Total Capital Investment Maint Mtls 0 % of Maintenance Labor NA 0 0% of Maintenan ce Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 1194.4 kW-hr 9,262,659 555,760 $/ kwh, 1,194 kW-hr, 8339.1 hr/yr, 93% utilization

Cat. Replacement [14] 35 $/MW-hr 85.5 mw 112 334,973 Catal yst Replacement

7 Ammonia 0.12 $/lb 167 lb/hr 1,297,437 156,470 $/lb, 167 lb/hr, 8339.1 hr/yr, 93% utilization

** Std Air use is 2 scfm/kacfm *annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 18: - Reheat (114)

Operating Unit: Furnace 12 Waste Gas

Emission Unit Number EU 114 Stack/Vent Number SV 104 & 105 Chemical Engineering Desgin Capacity 150 MMBtu/hr Standardized Flow Rate 152,520 scfm @ 32o F Chemical Plant Cost Index Expected Utiliztion Rate 93% Temperature 140 Deg F 1998/ 1999 390 Expected Annual Hours of Operation 8,339 Hours Moistur e Content 18.3% 2005 465 Annual Interest Rate 7.0% Actual Flow Rate 186,000 acfm Inflation Adj 1.19 Expected Equipment Life 20 yrs Standardized Flow Rate 1 63,680 scfm @ 68o F Dry Std Flow Rate 133,792 dscfm @ 68o F

CONTROL EQUIPMENT COSTS Capital Costs Direct Capital Costs Purchased Equipment (A) 512,555 Purchased Equipment Total (B) 22% of control device cost (A) 622,755

Installation - Standard Costs 30% of purchased equi p cost (B) 186,826 Installation - Site Specific Costs 6,200,000 Installation Total 6,386,826 Total Direct Capital Cost, DC 7,009,581 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 193,054 Total Capital Investment (TCI) = DC + IC 7,202,635

Operating Costs Total Annual Direct Operating Costs Labor, supervi sion, materials, replacement parts, utilities, etc. 4,772,459 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,023,490 Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 5,795,949

Notes & Assumptions 1 Equipment cost estimate EPA Air Pollution Control C ost Manual 6th Ed 2002, Section 3.2 Chapter 2.5.1 2 Calculations per EPA Air Pollution Control Cost Man ual 6th Ed 2002, Section 3.2 Chapter 2

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 18: - Reheat (114)

CAPITAL COSTS Direct Capital Costs Purchased Equipment (A) (1) 512,555 Purchased Equipment Costs (A) - Absorber + packing + auxillary equipment, EC Instrumentation 10% of control device cost (A) 51,256 MN Sales Taxes 6.5% of control device cost (A) 33,316 Freight 5% of control device cost (A) 25,628 Purchased Equipment Total (B) 22% 622,755

Installation Foundations & supports 8% of purchased equip cost (B) 49,820 Handling & erection 14% of purchased equip cost (B) 87,186 Electrical 4% of purchased equip cost (B) 24,910 Piping 2% of purchased equip cost (B) 12,455 Insulation 1% of purchased equip cost (B) 6,228 Painting 1% of purchased equip cost (B) 6,228 Installation Subtotal Standard Expenses 30% 186,826

Sitework and foundations Site Specific 1,400,000 Structural steel Site Specific 4,800,000 Site Specific - Other Site Specific 0 Total Site Specific Costs 6,200,000 Installation Total 6,386,826 Total Direct Capital Cost, DC 7,009,581

Indirect Capital Costs Engineering, supervision 10% of purchased equip cost (B) 62,275 Construction & field expenses 5% of purchased equip cost (B) 31,138 Contractor fees 10% of purchased equip cost (B) 62,275 Start-up 2% of purchased equip cost (B) 12,455 Performance test 1% of purchased equip cost (B) 6,228 Model Studies of purchased equip cost (B) 0 Contingencies 3% of purchased equip cost (B) 18,683 Total Indirect Capital Costs, IC 31% of purchased equip cost (B) 193,054

Total Capital Investment (TCI) = DC + IC 7,202,635

Adjusted TCI for Replacement Parts (Catalyst, Filte r Bags, etc) for Capital Recovery Cost 7,202,635



### OPERATING COSTS Direct Annual Operating Costs, DC
Operating Labor Operator 50.00 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr 26,060 Supervisor 15% 15% of Operator Costs 3,909 Maintenance Maintenance Labor 60.00 $/Hr, 0.5 hr/8 hr shift, 833 9.1 hr/yr 31,272 Maintenance Materials 100% of maintenance labor costs 31,272 Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.06 $/kwh, 689 kW-hr, 8339.1 hr/yr, 93% utilization 320,667 Natural Gas 10.02 $/mscf, 935 scfm, 8339.1 hr/yr, 93% utilizatio n 4,359,280

Total Annual Direct Operating Costs 4,772,459

Indirect Operating Costs Overhead 60% of total labor and material costs 55,507 Administration (2% total capital costs) 2% of total c apital costs (TCI) 144,053 Property tax (1% total capital costs) 1% of total cap ital costs (TCI) 72,026 Insurance (1% total capital costs) 1% of total capita l costs (TCI) 72,026 Capital Recovery 0.0944 for a 20- year equipment life and a 7% interest rate 679,878 Total Annual Indirect Operating Costs Sum indirect oper costs + capital recovery cost 1,023,490

Total Annual Cost (Annualized Capital Cost + Operat ing Cost) 5,795,949

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: United Taconite BART Report - <Insert attachment name> Emission Con trol Cost Analysis Table 18: - Reheat (114)

Capital Recovery Factors Primary Installation Interest Rate 7.00% Equipment Life 20 years CRF 0.0944

Replacement Catalyst: Catalyst Equipment Life 2 years CRF 0.5531 Rep part cost per unit 0 $/ft 3 Amount Required 39 ft 3 Catalyst Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 Assume Labor = 15% of catalyst c ost (basis labor for baghouse replacement) Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Replacement Parts & Equipment: Equipment Life 3 CRF 0.3811 Rep part cost per unit 0 $ each Amount Required 0 Number Total Rep Parts Cost 0 Cost adjusted for freight & sales tax Installation Labor 0 10 min per bag (13 hr total) Labor at $29.65/hr OAQPS list replacement times from 5 - 20 min per ba g. Total Installed Cost 0 Zero out if no replacement parts needed Annualized Cost 0

Electrical Use
Flow acfm **∆** P in H2O Efficiency Hp kW Blower, Thermal 186,000 19 0.6 689.1 EPA Cost Cont Manua l 6th ed - Oxidizders Chapter 2.5.2.1 Blower, Catalytic 186,000 23 0.6 834.2 EPA Cost Cont Man ual 6th ed - Oxidizders Chapter 2.5.2.1

Oxidizer Type thermal (catalytic or thermal) 689.1

Reagent Use & Other Operating Costs Oxidizers - NA

Operating Cost Calculations Annual hours of operatio n: 8,339 Utilization Rate: 93%

Unit Unit of Use Unit of Annual Annual Comments Item Cost $ Measure Rate Measure Use* Cost Operating Labor Op Labor 50.00 $/Hr 0.5 hr/8 hr shift 521 26,060 $/Hr, 0. 5 hr/8 hr shift, 8339.1 hr/yr Supervisor 15% of Op. NA 3,909 15% of Operator Costs Maintenance Maint Labor 60.00 $/Hr 0.5 hr/8 hr shift 521 31,272 $/Hr, 0.5 hr/8 hr shift, 8339.1 hr/yr Maint Mtls 100 % of Maintenance Labor NA 31,272 100% of Maintenance Labor Utilities, Supplies, Replacements & Waste Managemen t Electricity 0.060 $/kwh 689.1 kW-hr 5,344,453 320,667 $/k wh, 689 kW-hr, 8339.1 hr/yr, 93% utilization Natural Gas 10.02 $/mscf 935 scfm 435,040 4,359,280 $/msc f, 935 scfm, 8339.1 hr/yr, 93% utilization

*annual use rate is in same units of measurement as the unit cost factor

See Summary page for notes and assumptions

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## Cleveland Cliffs Incorporated: Northshore Mining BART Report - Appendix A Emission Control Cost Anal ysis Table 18: - Reheat (114)

Flue Gas Re-Heat Equipment Cost Estimate Basis The rmal Oxidizer with 70% Heat Recovery

Auxiliary Fuel Use Equation 3.19 T wi 140 Deg F - Temperature of waste gas into heat rec overy T fi 750 Deg F - Temperature of Flue gas into of heat r ecovery T ref 77 Deg F - Reference temperature for fuel combustio n calculations FER 70% Factional Heat Recovery % Heat recovery sect ion efficiency

T wo 567 Deg F - Temperature of waste gas out of heat r ecovery

T fo 323 Deg F - Temperature of flue gas into of heat r ecovery

-h caf 21502 Btu/lb Heat of combustion auxiliary fuel (met hane)
-h wg 0 Btu/lb Heat of combustion waste gas C p wg 0.2684 Btu/lb - Deg F Heat Capacity of waste gas (a ir) p wg 0.0739 lb/scf - Density of waste gas (air) at 77 De g F p af 0.0408 lb/scf - Density of auxiliary fuel (methane) at 77 Deg F Q wg 163,680 scfm - Flow of waste gas

Q af 935 scfm - Flow of auxiliary fuel

Year 2005 Inflation Rate 3.0% Cost Calculations 164,615 scfm Flue Gas Cost in 1989 $'s $429,885 Current Cost Using CHE Plant Cost Index $512,555 Heat Rec % A B

0 10,294 0.2355 Exponents per equation 3.24 0.3 13,149 0.2609 Exponents per equation 3.25 0.5 17,056 0.2502 Exponents per equation 3.26 0.7 21,342 0.2500 Exponents per equation 3.27

Indurator Flue Gas Heat Capacity - Basis Typical Co mposition

100 scfm 359 scf/lbmole Gas Composition lb/hr f wt % Cp Gas Cp Flue 28 mw CO 0 v % 0 44 mw CO2 15 v % 184 22.0% 0.24 0.0528 18 mw H2O 10 v % 50 6.0% 0.46 0.0276 28 mw N2 60 v % 468 56.0% 0.27 0.1512 32 mw O2 15 v % 134 16.0% 0.23 0.0368 Cp Flue Gas 100 v % 836 100.0% 0.2684

Reference: OAQPS Control Cost Manual 5th Ed Feb 1996 - Chapter 3 Thermal & Catalytic Incinerators (EPA 453/B-96-001)

Y:\23\00 MN Taconite BART (2006)\Facility BART Repo rts\NMC\NMC Furnace-Process Boiler\Appendices\Appen dix A - NMC Control Costs.xls Reheat (114) Reheat (114) 55 of 56InputsCalculated or scaled valuesEstimated value1 23 4 5 6 7 8 9Stack No Facility NameSO2Max. 24-hr ActualEmissionsFlow Rateat ExitSpecificCollection Area(SCA)1Surface CollectionArea2PressureDrop3Cost4lb/hr acfmft2/kacfmft2in. H20$BASEN/A291,00019868,82554,700,000SV 101, 102, & 103 Northshore Furnace 11 Hood Exhaust35.50 222,400 198 52,600 10 3,999,843SV 104 & 105 Northshore Furnace 11 Waste Gas 11.83 186,000 198 43,991 10 3,593,104SV 111, 112, & 113 Northshore Furnace 12 Hood Exhaust35.50 222,400 198 52,600 10 3,999,843SV 114 & 115 Northshore Furnace 12 Waste Gas 11.83 186,000 198 43,991 10 3,593,104SV021M-SV024M Hibbtac Pellet Indurating Furnace LineNo 1 30.00 772,000 198 182,587 10 8,439,806SV025M-SV028M Hibbtac Pellet Indurating Furnace LineNo 2 38.00 795,000 198 188,027 10 8,589,786SV029M-SV032M Hibbtac Pellet Indurating Furnace LineNo 3 43.00 827,000 198 195,595 10 8,795,598SV 014 Ispat Indurating Furnace 125.00 205,478 198 48,59810 3,814,356SV 015 Ispat Indurating Furnace 125.00 205,478 198 48,59810 3,814,356SV 016 Ispat Indurating Furnace 125.00 205,478 198 48,59810 3,814,356SV 017 Ispat Indurating Furnace 125.00 205,478 198 48,59810 3,814,356SV 046 UTAC Line 1 Pellet Induration 4.25 369,137 198 87,305 10 5,420,940SV 049 UTAC Line 2 Pellet Induration 286.67 380,000 198 89,875 10 5,516,101SV 048 UTAC Line 2 Pellet Induration 345.50 346,000 198 81,833 10 5,214,441SV051M Keetac Grate Kiln - Indurator Waste Gas, PhaseII 217.2 848,000 198 200,562 10 8,928,933SV 151 Minntac Line 7 waste gas 75.0 600,000 198 141,907 10 7,255,257SV 127 Minntac Line 5 waste gas 93.7 650,000 198 153,733 10 7,612,198SV 144 Minntac Line 6 waste gas 113.5 555,650 198 131,41810 6,928,558SV 118 Minntac Line 4 waste gas 133.1 650,000 198 153,73310 7,612,198SV 103 Minntac Line 3 waste gas 128.9 322,000 198 76,157 10 4,994,311NSM Power365.0 300,000 141,907 9,573,3691) Estimated value from Durr. Value indpendent ofstack flow.2) Original estimate from Durr. Scaled linearly using stack flow rates.3) Pressure drop is not a design driving factor, but must be maintained at an acceptably low value. 10" H2O is used as a maximum value.4) Capital price back calculated using reverse of EPA control cost manual factors from installed priceestimate provided from DURR.Used 0.6 power law factor to adjust price to each stack's acfm from bid basis of 291,000 acfm.Y:\23\00 MN Taconite BART (2006)\Facility BART Reports\NMC\NMC Furnace-Process Boiler\Appendices\Appendix A - NMC Control Costs.xlsWWESP Scale9/6/2006 Page 56 of 56