## MEMORANDUM January 25, 2010

To: F. Tanaka

Via: K. Kunaniec

From: T. Underwood

Re: Outside Test OS-3148; September 29, 30 and October 1, 2009 source test of emission point P-12 Site No: A0051 Plant No: 51; United Airlines Emission Pt: P-12 Source No: S-18, S-19; Plating tanks Abated by: A-218, A-219; Dry scrubber with composite mesh pads Abated by: A-418; HEPA A/C No: Title V Conditions: 23542, Reg. 11-8 incorporates CARB Table 94102.4 by reference*: Cr +6 0.0015 mg/A-hr *Note: Databank and the Title V permit would be clearer if the actual emission limit were cited directly. By: Blue Sky Environmental

I have reviewed the source test report cited above and note the following:

1) Source test was properly notified (NST-1811). 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. Despite sampling for six hours, the detection limit established was higher than the emission limit imposed on this source. Contributing factors could be laboratory error, handling error, or analyzer limitations. No retest is required. 5) Results of testing demonstrate these sources were in compliance with all of the conditions cited above.

This source was in compliance with District Regulations.

### TABLE 1 Hexavalent and Total Chromium Emission Test Results United Airlines San Francisco Maintenance Center Stack P-12 [Sources S-18 and S-19]

RUN # 1 2 3 AVERAGE LIMITS



### T EST DATE 9/29/09 9/30/09 10/1/09 

### T EST PERIOD 1053-1656 0724-1327 0856-1501 

### T EST DURATION, Mins 360 360 360 

### T otal Plating amp-hours 3,031 3,331 3,427 

### A verage amp-hr per hou r 505 555 571 

### SAMPLE VOLUME DSCF 198.162 199.132 200.689 

### ISOKINETIC % 100.4 98.1 100.1 99.5 

### DUCT TEMP °F 66.9 84.1 82.2 77.7 

### V ELOCIT Y ft/sec 41.90 44.45 43.43 43.26 

### FLOW RATE A CFM 7,895 8,375 8,182 8,151 

### FLOW RATE DSCFM 7,893 8,117 8,017 8,009 

### H 2 

### O % 1.06 0.96 0.89 0.97 

### O 2 

### % 20.90 20.90 20.90 20.90 

### CO 2 

### % 0.04 0.04 0.04 0.04 

### T otal Chromiu m ug <0.97 <1.40 <1.50 <1.29 

### T otal Chromiu m mg <0.00097 <0.00140 <0.00150 <0.00129 

### T otal Chromium mg/DSCM <0.000173 <0.000248 <0.000264 <0.000228 

### T otal Chromiu m gm/hr <0.0023 <0.0034 <0.0036 <0.0031 

### T otal Chromium (MW=51.996) 

### ppm <0.00008 <0.00011 <0.00012 <0.00011 

### Hexavalent Chromiu m ug <0.37 <0.41 <0.78 <0.52 

### Hexavalent Chromiu m mg <0.00037 <0.00041 <0.00078 <0.00052 

### Hexavalent Chromiu m mg/DSCM <0.000067 <0.000073 <0.000137 <0.000092 

### Hexavalent Chromiu m mg/hr <0.89 <1.01 <1.86 <1.26 

### Hexavalent Chromiu m mg/amp-h r <0.00177 <0.00181 <0.00326 <0.00228 

### Hexavalent Chromium (MW=51.996) 

### ppm <0.00003 <0.00003 <0.00006 <0.00004 Applicable Limit is based on United Airlines Permit to Operate Condition and CARB Chrome Plate ATCM Notes: Less than (<) signs precede the method detection limit.



### WHERE, CALCULATIONS, < = Less Than mg/DSCM = 35.314 * mg/DSCF Velocity = Stack gas velocity in feet per second gm/hr = 10 -6 * 60 * DSCFM * (ug/DSCM) / 35.314 DSCFM = Dry Standard cubic feet per minute mg/amp-hr = (mg/DSCF)*DSCFM*60/ave amp-hr per hr ug/DSCM = micrograms per dry standard cubic meter ppm @ 68°F = 24.05 * (mg/dscm) / M.W. gm/hr = Emission rate, grams per hour BLUE SKY ENVIRONMENTAL

0.015



### 0.0015

c:\documents and settings\blue sky\desktop\bluesky\2008 rpt\ual\ual m425 p-14 2008.xls - 1/26/2009