Laserfiche WebLink
6. Sample_Collection Procedures <br /> • Groundwater samples are collected as follows <br /> • A 1-liter Teflon bailer is lowered and partially submerged into the well water to <br /> collect a groundwater sample <br /> • If visible PSH is present in the sample bailer, PSH thickness is recorded on the <br /> field log, and no sample is collected for laboratory analysis. <br /> • For volatile organic analyses, groundwater samples are collected in chilled, <br /> 40-milliliter, VOA vials having Teflon-lined caps Hydrochloric acid preservative <br /> is added to all vials by the laboratory to lower sample pH to 2 Samples are held <br /> at 2 to 4°Celsius while in the field and in transit to the laboratory Other <br /> appropriate containers, preservatives, and holding protocols are used for <br /> non-volatile analyses <br /> • VOA vials are filled completely so that no headspace or air bubbles are present <br /> within the vial Care is taken so that the vials are not overfilled and the <br /> preservative is not lost <br /> • Sample containers are immediately labeled and sealed after collection to prevent <br /> confusion For VOA vials,the label is placed to overlap the edge of the cap as a <br /> custody seal, unless a separate custody seal is being used <br /> • Samples are stored in a cooler while on site and m transport to the laboratory or <br /> office The cooler has sufficient ice to maintain appropriate temperature prior to <br /> collecting samples.The VOA vials are kept cool both prior to and after filling <br /> Hot or warm containers are not used when volatile compounds are the target <br /> analytes. <br /> • 7. Decontamination Procedures <br /> Decontamination of monitoring and sampling equipment is performed prior to all <br /> monitoring and sampling activities Decontamination procedures utilize a three—step process as <br /> described below <br /> • The initial decontamination is performed using a non-phosphate soap, such as <br /> Simple Green or Alconox, in tap water in a 5-gallon bucket A soft-bristle <br /> bottlebrush is used to thoroughly clean the inside and outside of the equipment. <br /> • A second 5-gallon bucket of tap water is used as a first rinse <br /> • A third 5-gallon bucket of deiomzed water is used as a final rinse. <br /> • The brush is used in the first bucket only, it does not travel from bucket to bucket <br /> with the equipment This minimizes any transport of the contaminants that should <br /> stay in the first bucket <br />