ARCHIVED REPORTS XR0008205 - Laserfiche WebLink

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i ten inch or eight inch hollow stem augers. The drilling rig and augers are steam cleaned prior to use and all lubricated parts that were to enter or approach the boring were lubricated with olive oil. The sampling equipment is steam cleaned between each sampling interval. Boring logs are prepared by a Western Geo-Engineers field geologist, during the drilling and sampling. The samples are described and categorized using the Unified Sails Classification System and lithologic descriptions. Relatively undisturbed soil samples are collected at five-foot intervals using a California Split Spoon Sampler equipped with four 21IX6" clean brass sleeves. Borings are advanced to the desired depth with the hollow stem auger, then the center rod center plug pilot bit assembly is withdrawn. The sampler, attached to the centar rod, is then lowered through the auger to the bottom of the borehole and driven 18" into the soil with a 140-pound hammer. Prior to preservation, soil samples from each 3.nterval were field-checked for the presence of odor, vapor, and visible staining. Vapor analyses were performed with a hand-held photo ionizing detector (PID) , which was calibrated daily with a 25 ppm gasoline vapor standard. At each sample interval the brass sleeve containing the soil sample with the highest PID reading was immediately preserved and labeled. Samples are preserved by wrapping the sleeve ends with aluminium, P, ioLl and capping the ends with plastic caps, which were secured to the sleeve with duct tape. Each sleeve is labeled with time, date, hole number, depth, analyses to be run, the site name and initials of sampler. The sleeve is placed in a zip lock bag and then into an ice cheat containing dry ice to freeze the sample until hand delivered to a state-certifa.ed lab. Starting at fifteen feet below the surface, a sample from each five foot interval will be collected for field screening with appropriate samples being preserved and chain-of-custody delivered to a California certified laboratory. The samples will be tested for Total Petroleum Hydrocarbons (EPA 8015) , BTEX(EPA 8020) . WELL SURVEY Locations and elevations of the new wells are surveyed relative to the locations and elevations of the prior monitor wells, which have been surveyed to a known datum. WELL DEVELOPMENT The new monitor wells will be developed approximately 48 hours after completion. The wells will be developed by manually surging the wells over the entire length of the below writer slots with a plunger. Then purging the wells until it flows clean and the temperature, pH and conductivity have stabilized. •