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-. .r <br /> REM <br /> Coca-Cola Enterprises - West <br /> Job No. 90054 <br /> T A Hewlett Packard 5890 gas chromatograph, equipped with FID, was used for the soil gas <br /> analyses. The FII] is used to analyze for benzene, toiuene, xylenes, and total hydrocarbons. <br /> Xylenes are reported as the total of the three xylene isomers and total hydrocarbons are <br /> classified as gasoline range compounds (CeC,) consisting of aliphatic, alicyclic and aromatic <br /> compounds. Compounds were separated at 60°C on a 15-foot by 0.53u RT-5 Y Bere capillary <br /> column. Nitrogen was used as the carrier gas. <br /> Hydrocarbon compounds detected in soil gas are identified by chromatographic retention <br /> time. Quantification of compounds is achieved by comparison of the detector response of <br /> the sample with the response measured for calibration standards (external standardization). <br /> Instrument calibration checks are run periodically throughout the day and system blank <br /> are nu: prior to each s<-imple run to check for contamination in the soil gas sampling <br /> .', equipment. Air samples were also routinely analyzed to Check for background levels in the <br /> atmosphere. <br /> Detection limits for the compounds of interest are a function of the injection volume as well <br /> as the detector sensitivity for individual compounds. Thus, the detection limit varies with <br /> the sample size. Generally, the larger the injection size the greater the sensitivity. However, <br /> - peaks for compounds of interest must be kept within the linear range of the analytical <br /> equipment. If any compound has a high concentration, it is necessary to use small injections, <br /> and in some cases to dilute the sample to keep it within linear range. This may cause <br /> decreased detection limits for other compounds in the analyses. <br /> The detection limits.for the petroleum hydrocarbons were approximately 0.07 ng/ml, <br /> depending on the conditions of the measurement, in particular, the sample size. If any <br /> component being analyzed is not detected, the detection limit for that compound in that <br /> analysis is given as a "less than" value (e.g., <0.07 ng/ml). Detection limits obtained from <br /> GC analyses are calculated from the current response factor, thesample size, and the <br /> estimated minimum peak size (area) that would have been visible under the conditions of <br /> — measurement. <br /> 5 <br />