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either a centrifugal pump connected to a dedicated Watters pump or a pre-cleaned submersible pump, depending on depth to water and the amount of sediment expected to be contained in the well. Temperature, pH, and specific conductance of the purge water was monitored during the purging process at regular intervals. Purging was ceased when the monitored parameters stabilized (three consecutive readings not varying by more than 10-percent) and a minimum of three well volumes had been purged. In the event a well dried out during purging, the well was allowed to recover to 80-percent of it's original well volume, or for 24-hours, whichever was less, prior to collecting a groundwater sample Groundwater Monitoring Well Sampling Once the well was successfully purged a groundwater sample was collected using a disposable polyethylene bailer connected to clean nylon or polyethylene cord. The bailer was lowered slowly into the water to avoid agitation of the sample. A portion of the sample was placed in a container and the monitoring parameters were recorded. The remaining portion of the sample was transferred from the bailer to the appropriate, laboratory supplied sampling bottles, using a bottom emptying device. The sampling containers were filled completely, leaving a positive meniscus, so no airspace remained in the vial after sealing The sample bottles were labeled with the well identification (i.e. MW-1, MW-2, etc), date and time of the sample collection, the field technicians initials, ,lob number, analyses to be performed, and other relevant information. Samples were immediately placed in an insulated cooler containing crushed ice. The samples were maintained at approximately 3°C until reaching the analytical laboratory Laboratory Analysis Samples were shipped, under appropriate chain-of-custody procedures, to SPL Laboratory in Houston SPL Laboratory is certified by the State of California for performing the requested analyses. Samples were shipped via Federal Express to minimize the time the samples remained in the cooler Samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg), and benzene, toluene, ethylbenzene, and xylene isomers (BTEX), following Environmental Protection Agency Methods 5030, 8015 modified, and 8020. Samples were analyzed on a standard two week turn-around ,time. QA/QC'Procedures { I Instrument calibration Equipment used to monitor groundwater parameters was calibrated prior to beginning purging at the site Monitoring equipment was calibrated ! following the manufactures instructions using laboratory grade standards. �f Equipment Decontamination Non-disposable and non-dedicated sampling equipment was cleaned prior to use and betrveern uses in each well. Downhole equipment`was cleaned by ' I { �li t 'I°�I�� !��{� 1!1{�� fl it `I i � P{ r'!i