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2 <br /> GROUNDWATER SAMPLING PROTOCOL <br /> Prior to arriving at the sampling site, all sampling equipment is washed with laboratory grade <br /> detergent, and rinsed twice with tap water and once with deionized water This procedure is <br /> carred out on-site before sampling of other monitoring wells, if more than one'well is to be <br /> sampled with the sample sampling device <br /> I <br /> Immediately prior to sampling, the depth to water (DTW) in the well is recorded The <br /> thickness of product on top of the groundwater, if present, is measured using, an interface <br /> probe <br /> If free product is detected, analysis of groundwater at the interface for dissolved product is not <br /> conducted. A product sample is collected for source identification If all free product cannot <br /> be removed, an interval specific sampling device is often utilized to collect a sample from <br /> below the zone of free product Before collecting groundwater samples from each well, the <br /> well is purged until indicator parameters (temperature, conductivity, and pH) stabilize This <br /> entails the removal of three to five well casing volumes by bailing or pumping The indicator <br /> parameter measurements are taken both before and after purging of each well casing volumes <br /> Once the well is purged and indicator parameters have stabilized, a sample is collected after <br /> the water level approaches 80 percent of its initial elevation Where water level recovery is <br /> slow, the sample is collected after stabilization is achieved and enough water is present to fill <br /> sample containers <br /> Cross contamination from transferring pumps (or bailers) from well to well is avoided by <br /> utilizing dedicated equipment Where this is not feasible, thorough cleaning of equipment is <br /> performed between sampling rounds Sampling proceeds from the least contaminated to the <br /> most contaminated well, if information is available before sample collection; or if it is <br /> indicated by field evidence. Where several types of analyses are performed for a given well, <br /> individual samples are collected in the following order <br /> 1 Volatile Organics <br /> 2 Purgeable Organic Carbon <br /> 3 Purgeable Organic Halogens <br /> 4 Total Organic Carbon <br /> 5. Total Organic Halogens <br /> 6 Extractable Organics <br /> 7. Total Metals <br /> 8 Dissolved Metals <br /> 9. Phenols <br /> 10 Cyanide <br /> Groundwater samples are collected with a disposable bailer with a bottom emptying device <br /> Duplicate samples are transferred to vials or containers that meet Regional Board <br /> specifications. Groundwater from the bailer is transferred to the sample container by allowing <br /> i <br /> GKRAMERISHELLSIQA-CHEVR DOC CanonieEnvlronmental <br /> i <br /> I <br />