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q} <br /> • samples for chemical analysis were retained in the brass liners, labeled, and capped with <br /> Teflon sheets and plastic end caps The samples were then sealed in zip-lock bags, placed on <br /> ice, and transported to the laboratory accompanied by the appropriate chain-of-custody <br /> documentation <br /> Laboratory Analysis for Soil Samples <br /> Analyses for TPHg, benzene, toluene, ethylbenzene, xylenes (BTEX compounds), and MtBE <br /> were performed by EPA Method 8015/8020 Fuel Oxygenates were analyzed by EPA <br /> Method 8260 Analysis for lead was done using EPA method 6010A <br /> Groundwater Sampling Procedures <br /> The sampling procedure for each well consists first of developing the well by purging <br /> approximately 10 casing volume of water from the well Sampling consisted of measuring the <br /> water level and checking for the presence of separate-phase hydrocarbons (SPH), using either <br /> an electronic indicator and a clear Teflon® bailer or an oil-water interface probe Wells that <br /> have submerged screens are purged of approximately three casing volumes of water (or to <br /> dryness) using a centrifugal pump, gas displacement pump, or bailer Equipment and purging <br /> method used for the current sampling event is noted on the attached field data sheets During <br /> purging, temperature, pH, and electrical conductivity are monitored in order to document that <br /> these parameters are stable prior to collecting samples After purging, water levels are <br /> allowed to partially recover Groundwater samples (both purge and no purge) are collected <br /> using a Teflon baler, placed into appropriate EPA-approved containers, labeled, logged onto <br /> chain-of-custody documents, and transported on ice to a California State-certified laboratory <br /> Laboratory Procedures for Groundwater Samples <br /> The groundwater samples were analyzed for the presence of total petroleum hydrocarbons <br /> calculated as gasoline, benzene, toluene, ethylbenzene, xylenes, and MtBE by EPA Method <br /> 8015/8020 Fuel oxygenates were analyzed by EPA Method 8260 These analyses were <br /> performed by utilizIncy a purge and trap extraction technique, with final detection was by gas <br /> chromatography using flame- and photo-ionization detectors The methods of analysis for the <br /> groundwater samples are documented in the certified analytical report The certified analytical <br /> report, chain-of-custody documentation, and field data sheets are presented as Attachment C <br /> i <br />