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i r <br /> i I � <br /> 4- <br /> ' STANDARD OPERATING PROCEDURE <br /> GROUNDWATER SAMPLING <br /> r <br /> r r <br /> Gettler-Ryan Inc field personnel adhere to the following procedures for the collection and handling <br /> of groundwater samples pnor to analysis by the analytical laboratory Prior to sample collection, the <br /> type of analysis to be performed is determined Loss prevention of volatile compounds is controlled <br /> and sample preservation for subsequent analysis is maintained. <br /> Prior to sampling, the presence or absence of free-phase hydrocarbons is determined using an <br /> interface probe Product thickness, if present, is measured to the nearest 0 01 foot and is noted in the <br /> field notes In addition, all depth to water level measurements are collected with a static water level <br /> indicator and are'also recorded in the field notes, prior to purging and sampling any wells <br /> After water levels are,collected and prior to sampling, if purging is to occur, each well is purged a <br /> minimum of three well casing volumes of water using pre-cleaned pumps (stack, suction, Grundfos), <br /> or disposable bailers Temperature, pH and electrical conductivity are measured a minimum of three <br /> times during the purging Purging continues until these parameters stabilize <br /> .r..,.. .. r .. t ~r i s, <br /> Groundwater samples are collected using disposable bailers. The water samples are transferred from <br /> the bailer into appropriate containers Pre-preserved containers, supplied by analytical laboratories, <br /> are used when possible When pre-preserved containers are not available, the laboratory is instructed <br /> to preserve the sample as appropriate Duplicate samples are collected for the laboratory to use in <br /> maintaining quality assurance/quality control standards The samples are labeled to include the job <br /> number, sample idenufication, collection date and time, analysis, preservation (if any), and the <br /> sample-collector-_'s-inmals The_water__samples-are-placed_in-a-cooler,_m amtained_at 4°C for transport <br /> to the laboratory Once collected in the field, all samples are maintained under chain of custody until <br />----_—delivered to the=laboratory ----- -- --— ------- --- <br /> The chain of custody document includes the )ob number, type of preservation,if any,analysis---�� -- <br /> requested, sample identification, date and time collected, and the sample collector's name The chain <br /> of custody is signed and dated (including time of transfer) by each person who receives or surrenders, <br /> the samples, beginning with the field personnel and ending with the laboratory personnel. <br /> A laboratory supplied trip blank accompanies each sampling set and is labeled QA For sampling <br /> sets greater than 20 samples, 5% trip blanks are included The trip blank is analyzed for some or all <br /> of the same compounds as the groundwater samples <br /> As requested by Unocal Corporation, the purge water and decontamination water generated during <br /> sampling activities is transported to Tosco - San Francisco Area Refinery, located in Rodeo, <br /> California <br /> hVorwlanomisW fmWOV21l03 <br />