Cliffs Natural Resources Barr Engineering Co.

Hibbing Taconite Company October 22, 2010

Hibbing, Minnesota

 Emissions Calculations

SV024 Stack A

Airflow Rates Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9

DSCFM 142,166 144,632 144,038 144,186 142,217 142,441 141,079 142,340 142,943

NOIx bias corrected ppm 87 88 87 87 89 87 91 88 87

Emission Calculations

NOx lb/hr 89.1 91.4 89.3 90.1 90.2 89.1 91.7 89.7 89.3

SV023 Stack B

Airflow Rates Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9

DSCFM 146,343 149,216 150,026 150,229 149,157 147,881 147,895 146,794 148,130

NOIx bias corrected ppm 78 79 77 79 79 79 81 79 79

Emission Calculations

NOx lb/hr 82.1 84.6 83.1 84.8 84.4 83.3 86.2 83.0 83.3

SV022 Stack C

Airflow Rates Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9

DSCFM 159,200 158,500 159,000 158,700 157,000 157,800 157,400 156,200 157,800

NOIx bias corrected ppm 55 56 53 55 54 55 56 55 54

Emission Calculations

NOx lb/hr 62.3 63.4 60.3 62.1 60.4 61.8 63.6 61.8 61.3

SV021 Stack D

Airflow Rates Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9

DSCFM 162,924 163,076 163,231 161,977 162,975 160,562 160,251 161,932 162,071

NOIx bias corrected ppm 47 48 45 47 46 47 48 47 47

Emission Calculations

NOx lb/hr 54.8 56.5 53.2 55.0 53.6 54.3 55.3 54.7 54.4

Line 1 During Low Fire Conditions
Cliffs Natural Resources Barr Engineering Co.

Hibbing Taconite Company October 22, 2010

Hibbing, Minnesota

Results of the Nitrogen Oxides Relative Accuracy Test Audit

Testing performed on May 3, 2010

Test Condition: Furnace Line 1 Mid Temperature Firing Condition

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10 Run 11

SV024 Stack A 1050-1111 1128-1149 1205-1226 1240-1301 1316-1337 1403-1424 1436-1457 1513-1534 1549-1610 1628-1649 1705-1726

Ref. Method lb/hr 107.8 105.0 106.1 102.5 113.6 111.4 112.9 118.2 118.3 114.2 118.9

PEM lb/hr 144.6 146.6 148.8 144.3 146.2 143.7 146.5 142.4 142.6 146.4 144.2

Difference 36.8 41.5 42.8 41.8 32.6 32.3 33.6 24.2 24.2 32.3 25.3

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10 Run 11

SV023 Stack B 1050-1111 1128-1149 1205-1226 1240-1301 1316-1337 1403-1424 1436-1457 1513-1534 1549-1610 1628-1649 1705-1726

Ref. Method lb/hr 100.0 98.3 100.0 98.4 107.9 104.3 105.9 110.5 111.4 107.9 110.4

PEM lb/hr 138.3 136.5 139.5 139.5 140.2 133.2 131.9 134.7 135.5 138.1 139.4

Difference 38.3 38.2 39.5 41.1 32.3 28.9 26.0 24.2 24.1 30.1 29.0

NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10 Run 11

SV022 Stack C 1050-1111 1128-1149 1205-1226 1240-1301 1316-1337 1403-1424 1436-1457 1513-1534 1549-1610 1628-1649 1705-1726

Ref. Method lb/hr 73.6 72.4 71.7 72.6 77.8 75.7 77.2 81.0 80.0 77.8 81.3

PEM lb/hr 106.9 110.6 110.8 111.9 108.7 109.1 108.5 109.5 107.7 112.6 110.3

Difference 33.3 38.2 39.1 39.3 30.9 33.4 31.3 28.4 27.8 34.8 29.0

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10 Run 11

SV021 Stack D 1050-1111 1128-1149 1205-1226 1240-1301 1316-1337 1403-1424 1436-1457 1513-1534 1549-1610 1628-1649 1705-1726

Ref. Method lb/hr 66.1 64.4 63.4 63.7 67.0 67.4 68.4 72.2 70.0 68.4 70.7

PEM lb/hr 106.7 105.2 107.2 106.8 107.3 103.1 101.6 107.0 107.9 108.3 108.9

Difference 40.6 40.8 43.8 43.1 40.3 35.7 33.2 34.8 37.9 39.9 38.3
Cliffs Natural Resources Barr Engineering Co.

Hibbing Taconite Company October 22, 2010

Hibbing, Minnesota

Pellet Indurating Furnace Line 1

Testing performed on May 4, 2010

Test Condition: Furnace Line 1 High Temperature Firing Condition

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10

SV024- Stack A 730-0751 810-0831 843-0904 1008-1029 1047-1108 1123-1144 1157-1218 1230-1251 1302-1323 1337-1358

Ref. Method %, dry 125.4 127.9 126.7 121.8 124.5 122.8 122.3 123.8 127.6 125.9

CEM %, dry 158.3 155.0 153.4 153.1 153.8 151.8 150.5 150.4 149.5 149.8

Difference 32.9 27.1 26.7 31.4 29.3 29.0 28.1 26.6 21.9 23.9

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10

SV023 Stack B 730-0751 810-0831 843-0904 1008-1029 1047-1108 1123-1144 1157-1218 1230-1251 1302-1323 1337-1358

Ref. Method %, dry 115.3 117.5 117.0 113.2 116.2 116.4 115.9 114.5 120.8 118.6

CEM %, dry 152.4 149.8 149.1 144.7 151.7 146.0 144.6 147.7 140.4 141.5

Difference 37.2 32.2 32.1 31.5 35.6 29.6 28.6 33.2 19.6 22.9

NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10

SV022 Stack C 730-0751 810-0831 843-0904 1008-1029 1047-1108 1123-1144 1157-1218 1230-1251 1302-1323 1337-1358

Ref. Method lb/hr 83.1 89.6 85.7 85.2 85.5 84.6 85.7 83.1 88.1 84.1

CEM lb/hr 114.3 116.0 111.4 113.1 116.4 113.4 117.0 113.5 111.9 110.0

Difference 31.2 26.4 25.6 27.9 30.9 28.9 31.3 30.5 23.8 25.9

 NOx Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Run 7 Run 8 Run 9 Run 10 

SV021 Stack D 730-0751 810-0831 843-0904 1008-1029 1047-1108 1123-1144 1157-1218 1230-1251 1302-1323 1337-1358

Ref. Method lb/hr 74.2 79.8 75.7 75.6 77.5 76.0 77.7 74.6 79.6 75.7

CEM lb/hr 109.6 108.0 107.4 105.5 110.6 107.3 106.6 108.3 108.3 109.4

Difference 35.4 28.2 31.7 29.9 33.1 31.3 28.9 33.7 28.7 33.8

All Data