### MEMORANDUM April 13, 2009

To: P. Leong

Via: K. Kunaniec

From: T. Underwood
Re: Outside Test OS-2766; February 10 and 11, 2009 source test of S-82 Re: Outside Test OS-2767; February 10 and 11, 2009 source test of S-93 Re: Outside Test OS-2768; March 17 and 18, 2009 source test of S-93 Re: Outside Test OS-2769; March 9 and 10, 2009 source test of S-155 Site No: A2371 Plant No: 2371; USS POSCO A/C No: Title V Source No: S-82; Electro-tinning line Abated by: A-41; Scrubber Source No: S-93; No. 3 Electro-tinning line Abated by: A-42; Scrubber Source No: S-155; Electro-tinning line #1, Chrome plating bath Abated by: A-41; Scrubber Cond. No. 7579; Cr +6 

### 0.0015 mg/A-hr enforceable after October 24, 2009; Cr +6 

### 0.006 mg/A-hr By: Avogadro Group

I have reviewed the source test r eport cited above and note the following:
1) Source test was properly notif ied (NST-1624, NST-1644, and NST-1654). 2) I did not witness the tests. 3) The testing appears to have been conducted by personnel who are familiar with proper source testing techniques. 4) Quality assurance procedures were adequate to assure data integrity. 5) Results of that testing are that quantified emissions were in compliance with the emission limits cited above.
These sources were in compliance with District Regulations.

### USS POSCO Industries March 24, 2009 2009 Source Test Report

09079.1, .2 & .6c 15 

### TABLE 5-1 RESULTS SUMMARY USS POSCO INDUSTRIES S-82 ELECTRO-TINNING LINE #1

Test No.: 1-Cr-ETL 1 2-Cr-ETL 1 3-CrETL 1 Average

Date: 2/10/09 2/10/09 2/11/09 Time: 0935-1237 1302-1504 0903-1400
Flue Gas:

Sample Volume, dscf 117.05 118.75 115.67 117.16 O 2 , % volume dry 20.71 20.72 20.48 20.64 CO 2 , % volume dry 0.04 0.03 0.06 0.04 Total ampere-hour 12,936 13,728 8,712 11,792 Stack gas temperature  F 67.9 71.6 70.8 70.1 Moisture content, % vol. 2.09 2.45 2.29 2.28 Stack flow rate, dscfm 13,227 13,390 13,568 13,395
Total Chromium: ug/dscm 0.2051 0.2349 0.2015 0.2138 lb/hr 1.02E-05 1.18E-05 1.02E-05 1.07E-05 mg/amp-hr 0.0011 0.0012 0.0016 0.0013
Hexavalent Chromium: ug/dscm 0.0875 0.0684 0.0580 0.0713 lb/hr 4.33E-06 3.43E-06 2.95E-06 3.57E-06 mg/amp-hr 0.0005 0.0003 0.0005 0.0004

### USS POSCO Industries March 24, 2009 2009 Source Test Report

09079.1, .2 & .6c 16 

### TABLE 5-2 RESULTS SUMMARY USS POSCO INDUSTRIES S-93 ELECTRO-TINNING LINE #3

Test No.: 1-Cr-ETL 3 2-Cr-ETL 3 3-Cr-ETL 3 Average

Date: 2/10/09 2/11/09 2/11/09 -- Time: 1315-1616 1102-1423 1427-1728 --
Flue Gas:

Sample Volume, dscf 107.17 104.28 106.15 105.87 O 2 , % volume dry 20.53 20.33 20.29 20.38 CO 2 , % volume dry 0.06 0.05 0.03 0.046 Total ampere-hour 3,564 3,630 3,630 3,608 Stack gas temperature,  F 83.7 83.8 86.3 84.6 Moisture content, % vol. 2.45 2.98 2.95 2.79 Stack flow rate, dscfm 11,141 11,109 11,076 11,109
Total Chromium: ug/dscm 0.4613 0.2438 0.2362 0.3137 lb/hr 1.92E-05 1.01E-05 9.79E-06 1.31E-05 mg/amp-hr 0.0074 0.0038 0.0037 0.0049
Hexavalent Chromium: ug/dscm 0.2735 0.0677 0.0632 0.1348 lb/hr 1.14E-05 2.82E-06 2.62E-06 5.61E-06 mg/amp-hr 0.0044 0.0011 0.0010 0.0021

### USS POSCO Industries March 24, 2009 2009 Source Test Report

09079.1, .2 & .6c 17 

### TABLE 5-3 RE-TEST RESULTS SUMMARY USS POSCO INDUSTRIES S-93 ELECTRO-TINNING LINE #3

Test No.: 1-Cr-RT 2-Cr-RT 3-Cr-RT Average

Date: 3/17/09 3/17/09 3/18/09 -- Time: 0820-1121 1127-1428 0822-1123 --
Flue Gas:

Sample Volume, dscf 121.34 120.25 120.25 120.62 O 2 , % volume dry 20.93 20.95 20.87 20.91 CO 2 , % volume dry 0.086 0.204 0.059 0.116 Total ampere-hour 4,620 4,356 4,290 4,422 Stack gas temperature,  F 91.1 91.9 91.9 91.6 Moisture content, % vol. 3.26 3.19 3.19 3.21 Stack flow rate, dscfm 10,411 10,466 10,470 10,449
Total Chromium: ug/dscm 0.1862 0.3230 0.1586 0.2226 lb/hr 7.26E-06 1.27E-05 6.21E-06 8.71E-06 mg/amp-hr 0.0021 0.0040 0.0020 0.0027
Hexavalent Chromium: ug/dscm 0.0141 0.0774 0.0710 0.0542 lb/hr 5.51E-07 3.03E-06 2.78E-06 2.12E-06 mg/amp-hr 0.0002 0.0009 0.0009 0.0007

### USS POSCO Industries March 24, 2009 2009 Source Test Report

09079.1, .2 & .6c 18 

### TABLE 5-4 RESULTS SUMMARY USS POSCO INDUSTRIES S-155 ELECTRO-TINNING LINE #1 TFS

Test No.: 1-Cr-ETL 1 2-Cr-ETL 1 3-Cr-ETL 1 Average

Date: 3/9/09 3/10/09 3/10/09 -- Time: 1201-1502 1115-1452 1500-1801 --
Flue Gas:

Sample Volume, dscf 116.31 119.28 116.10 117.23 O 2 , % volume dry 20.90 20.90 20.90 20.90 CO 2 , % volume dry 1.00 1.00 1.00 1.00 Total ampere-hour 82,200 89,100 84,600 85,300 Stack gas temperature  F 84.3 84.7 85.8 84.9 Moisture content, % vol. 3.56 3.48 3.81 3.61 Stack flow rate, dscfm 9,339 9,367 9,321 9,342
Total Chromium: ug/dscm 0.2307 0.2812 0.2220 0.2447 lb/hr 8.065E-06 9.859E-06 7.746E-06 8.56E-06 mg/amp-hr 0.0001 0.0002 0.0001 0.0001
Hexavalent Chromium: ug/dscm 0.0692 0.0870 0.0766 0.0776 lb/hr 2.42E-06 3.05E-06 2.67E-06 2.71E-06 mg/amp-hr 0.00004 0.00005 0.00004 0.00004