Laserfiche WebLink
STANDARD OPERATING PROCEDURE - <br /> GROUNDWATER SAMPLING <br /> Gettler-Ryan Inc field personnel adhere to the following procedures for the collection and handling of <br /> groundwater samples prior to analysis by the analytical laboratory Prior to sample collection, the type <br /> of analysis to be performed is determined Loss prevention of volatile compounds is controlled and <br /> sample preservation for subsequent analysis is maintained <br /> Prior to sampling, the presence or absence of free-phase hydrocarbons is detennined using an interface <br /> probe Product thickness, if present, is measured to the nearest 0 01 foot and is noted in the field notes <br /> In addition, static water level measurements are collected with the interface probe and are also recorded <br /> in the field notes <br /> After water levels are collected and prior to sampling, each well is purged a minimum of three well <br /> casing volumes of water using pre-cleaned pumps (stack, suction, Grundfos), or polyvinyl chloride <br /> bailers Temperature, pH and electrical conductivity are measured a minimum of three times during the <br /> purging Purging continues until these parameters stabilize <br /> Groundwater samples are collected using Chevron-designated disposable bailers The water samples are <br /> transferred from the bailer into appropnate containers Pre-preserved containers, supplied by analytical <br /> laboratories, are used when possible When pre-preserved containers are not available, the laboratory is <br /> instructed to preserve the sample as appropriate Duplicate samples are collected for the laboratory to <br /> use in maintaining quality assurance/quality control standards The samples are labeled to include the <br /> fob number, sample identification,collection date and time, analysis, preservation (if any), and the sample <br /> collector's initials The water samples are placed in a cooler, maintained at 4oC for transport to the <br /> laboratory Once collected in the field, all samples are maintained under chain of custody until delivered <br /> to the laboratory <br /> The chain of custody document includes the fob number,type of preservation, if any, analysis requested, <br /> sample identification, date and time collected, and the sample collector's name The chain of custody is <br /> signed and dated (including time of transfer) by each person who receives or surrenders the samples, <br /> beginning with the field personnel and ending with the laboratory personnel <br /> A laboratory supplied trip blank accompanies each sampling set For sampling sets greater than 20 <br /> samples,5%trip blanks are included The tnp blank is analyzed for some or all of the same compounds <br /> as the groundwater samples <br /> As requested by Chevron Products Company, the purge water and decontamination water generated <br /> during sampling activities is transported by IWM to McKittrick Waste Management located in <br /> McKittrick, California <br /> N 4Cahformalfomisu trevron SOP 10100 <br />