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GSI Field Methods and Procedures February 14, 1995 is monitored for the presence of floating product and the depth-to-water is recorded Wells are then developed by alternately surging the well with a bailer, then purging the well with a pump to remove accumulated sediments and draw groundwater into the well Development continues until the groundwater parameters (temperature, pH, and conductivity) have stabilized Groundwater removed from the well during development is stored at the site in approved sealed drums pending disposal Wells are allowed to stand a minimum of 24 hours after development before being sampled Prior to sampling, well casing water and interstitial water in the artificial sand pack of each well are purged using a pump or bailer The type of equipment used to purge the well is chosen based on well size, depth, location, accessibility, chemical constituents, and client or regulatory recommendations Generally, three to five casing volumes are typically purged prior to sample collection Wells that dewater or demonstrate low yield will not be sampled unless the well recharges to at least 80% of the previously measured water column Temperature, pH, and specific conductivity of the discharged water are monitored during purging Purging continues until groundwater parameters have stabilized Purged well water is stored at the site in approved sealed drums pending disposal Groundwater samples are collected from the well with either a disposable teflon bailer or a pneumatic bladder pump The sampling device is chosen based on the well criteria outlined above Groundwater samples are collected in laboratory-prepared containers After sample collection, the sample bottles are sealed, labelled, and entered on a chain-of-custody form The sample bottles are then packed in protective foam or bubble-wrap and placed in a cooler with blue ice for transport to the analytical laboratory If previous sampling data is available, the wells at a site are generally sampled from the least contaminated to the most contaminated Well purging and sampling equipment are decontaminated between wells and between sites using a high-pressure wash of potable water and Alconox® soap, followed by a rinse in potable water and then distilled water Storing and Sampling of Drill Cuttings Drill cuttings are stockpiled on plastic sheeting or stored in drums depending on site conditions and regulatory requirements Stockpile samples are collected and analyzed on the basis of one composite sample per 50 cubic yards of soil Stockpile samples are composed of four discrete soil samples, each collected from an arbitrary location on the stockpile The four discrete samples are then composited in the laboratory prior to analysis Each discrete stockpile sample is collected by removing the upper 3 to 6 inches of soil, and them driving the stainless steel or brass sample tube into the stockpiled material with a hand, A-3 GeoStrategies Inc.