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ANALYTICAL METHODOLOGY <br /> Volatile Organics <br /> The analytical techniques used for water and soil analysis are based on EPA <br /> Methods 624 and 8240 (Purgeables) and follow EPA Contract Laboratory <br /> Program (CLP) recommendations. Water and soil samples are analyzed by a <br /> purge and trap, packed column GC/MS technique. The samples are analyzed <br /> under full scan GC/MS which monitors a mass range of 35-260. <br /> Water - <br /> A 5 ml sample volume to which 3 internal standards and 3 surrogates are <br /> added and purged with helium at ambient temperature. The sample is <br /> collected on a Tenax silica gel trap and then desorbed onto a packed <br /> column. <br /> i <br /> Soil/Sludge: Low - <br /> A 5 gram sample weight is added to 5 mis of reagent water containing 3 <br /> internal standards and 3 surrogates and purged with helium at 400C. <br /> Soil/Sludge: Medium - <br /> A 5 gram sample is weighed into a QA/QC prepped VOA vial and then <br /> shaken with 10 ml methanol. A 100 ul portion of the methanolic extract is <br /> combined with 5 ml of water. Surrogates and internal standards are added, <br /> and the sample analysis then follows the water protocol. <br /> The 5 gram samples used for analysis are a mix taken from the top, middle <br /> and bottom of the sample container. This mix was used to ensure that the <br /> analysis represented an accurate analysis of a non-homogenous soil/sludge <br /> sample. <br /> Tuning and Blanks <br /> The samples are run after meeting GC/MS hardware tuning ion abundance <br /> criteria, using p-Bromofluorobenzene (BFB) for volatiles. Laboratory blanks <br /> are run each day and a trip blank is also analyzed. <br /> r <br /> CHEMWEST ANALYTICAL LABORATORIES,INC. <br />