ARCHIVED REPORTS_TEMPORARY SOIL GAS PROBE PERMIT APPLICATION PACKAGE

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' SOP TO-14A/15 Rev 4 December 2007 ' Secondary standards for TO-14A/15 analysis will be prepared and given expiration dates not to exceed the manufacturer's date of expiration on the primary standard. The lab operator should monitor response factors to determine whether standards are ' degrading. In general, response factors will vary with tuning characteristics. However,comparison to response factors from fresh standard is suggested. ' 8.0 Method Calibration In order to analyze samples the instrument must first be calibrated. The following subsections describe the ' system start-up and initial calibration procedures. 8.1 Initial System Calibration ' Prior to performing analyses, the GC-MS must be tuned and calibrated to ensure system precision and accurate results. Tuning of the GC-MS is accomplished using the Agilent Target Tune function in the BFB tune mode. The instrument automatically performs the tuning in an attempt to adjust parameters such that the spectrum of the ' compound 1,4-Bromofluorobenzene will meet the following specifications: • Mass 50 15 percent to 40 percent of mass 95 ' 0 Mass 75 30 percent to 60 percent of mass 95 • Mass 95 base peak, 100 percent relative abundance Mass 96 5 percent to 9 percent of mass 95 ' 0 Mass 173 less than 2 percent of mass 174 • Mass 174 greater than 50 percent of mass 95 • Mass 175 5 percent to 9 percent of mass 174 ' 0 Mass 176 greater than 95 percent, but less than 101 percent of mass 174 • Mass 177 5 percent to 9 percent of mass 176 ' Following tuning, 50 ng of BFB or less should be evaluated in the next blank or standard to determine the validity of the tune. Since BFB is one of the surrogate compounds that are included in every analysis, it can ' be monitored following any analysis. (See section 11.0 for details.) If the above criteria are not met,the instrument must be retuned or the problem found prior to proceeding. ' Prior to performing analyses, the GC-MS must be calibrated to ensure system precision and accurate results. To calibrate the GC-MS, standards of the analytes, along with intemal standards and surrogates are introduced into the concentrator and measured by the method. A minimum of five concentration levels should be used during calibration for EPA Method TO-14A/15. (For TO-14A, three level are required, for TO-15, five levels are used.) Each standard level is analyzed under the identical parameters as samples will be analyzed. The end result is a calibration curve for each analyte. (Note: Certain regulatory protocols i.e. LARWQCB and specific client Data Quality Objectives(DQOs)may require fewer than five initial calibration standards) ' Page 7 of 24