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& � �� • � _ t dam..�. � r � ;,�`"�_ .a rl � - �, � F' .�', u Eli ,""tG r EAI 9 101 18cl Pane 2 of 15 The samples were analyzed for purgeable organic compounds according to U.S. EPA Method 8240 (Test Methods for Evaluating Solid Waste - SW846, 3rd Ed. ,1986) . Results are presented in Table 3. The method can be summarized as follows: Helium is bubbled through a measured aliquot of sample in organic free water contained in a sjecially designed purging chamber. The purgeable volatile organic compounds are efficiently transferred from the aqueous phase to the vapor phase. The vapor is swegt through a sorbent column where the purgeables are trapped. After purging is completed, the trap is heated and back flushed with helium to desorb the purgeables onto a gas chromatographic column. The gas chromatograph is temperature programmed to separate the purgeables that are then detected with a mass spectrometer. The samples were analyzed for semivolatile organic compounds according to U.S. EPA Method 8270 (Test Methods for Evaluating Solid Waste - SW846, 3rd Ed. ,1986) . Results are presented in Table 4. The method can be summarized as follows: A measured/weighed aliquot of sample is extracted with methylene chloride (aqueous samples) or methylene chloride/acetone (1:1) (solid samples) at a method specified pH. The extract is dried using sodium sulfate and concentrated to 1 mL. Just prior to injection into a Gas Chromatograph/Mass Spectrometer (GC/MS) , internal standards are added. The GC/MS is equipped with a fused silica capillary column and is set up for the analysis of semivolatile priority pollutants. Qualitative identification of the priority pollutants is performed initially using the relative retention times and the relative abundance of three unique ions. The entire mass spectrum is checked before anyed final identifications are recorded. Quantitative analysis is p by the internal standard method using a single characteristic ion and response factors obtained from a daily calibration standard. In the tables, an entry such as "<5" means that the compound was not found at a level above the laboratory's reporting limit. The reporting limit, which is based on EPA reporting levels, has been corrected for any sample dilution. Prior to analysis, every sample is spiked with surrogate compounds as part of Mid-Pacific's Quality Control Program. These compounds simulate the behavior of compounds of interest and confirm that acceptable recoveries are being a,:hievcd on every sample. The results of surrogate recoveries are reported with the sample results.