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Groundwater Grab Sample Collection Groundwater samples will be collected using the Hydropunch groundwater sampling system. The Hydropunch operates by pushing 1.75- or 1.5-inch diameter hollow rods with a retrievable tip. A stainless steel filter screen is attached to the tip. At the desired sampling depth, the rods are retracted, exposing the filter screen and allowing for groundwater infiltration. A small diameter bailer is then used to collect groundwater samples through the hollow rod. The bailer will be washed between sample intervals using a bristle brush with Alconox solution followed by two tap water rinses and one distilled water rinse. The bailers will be dried by air or with paper towels prior to sampling. One duplicate groundwater grab sample will be collected for every 10 samples. One equipment rinse blank sample will be collected each day. Rinse blank samples will be collected by passing distilled water through a washed bailer into the sample containers. Duplicate sample and equipment rinse blank sample locations will be selected to provide coverage across the investigation area. The duplicate samples and equipment rinse blank samples will be analyzed for chloroform and carbon tetrachloride. One trip blank will be carried in an ice chest for each day of the field investigation. The trip blanks will be analyzed for chloroform and carbon tetrachloride. The CPT/Hydropunch holes will be grouted by one of two options: 1)by pushing a hollow CPT rod with a"knock" out plug back down the hole to test termination depth; grout is then pumped under pressure as the tremie pipe is pulled from the hole;or 2)using retractive grouting whereby the grout is pumped into the annular space around the cone rods as the cone is penetrated into the subsoil; the grout fills the hole as the cone penetrometer is retracted. Sample Retention and Analysis All samples will be placed on ice in an insulated chest cooled to a temperature of approximately 4 degrees Celsius. Chain of custody procedures, including the use of chain of custody forms,will be used to document sample handling and transport from collection to delivery to the laboratory for analysis. The samples will be retained in the insulated chests preserved with ice overnight in the custody of an IT employee. The samples will be picked up within approximately 24 hours of collection by a courier supplied by the laboratory, or will be delivered to the laboratory by IT personnel within approximately 24 hours of collection. The samples will be transported to the laboratory in a motor vehicle. Upon receipt of the samples by the laboratory,the laboratory will record the internal temperature of the chests on the chain-of-custody forms. IT Corporation Work Plan Page A - 2 All Pure,Tracy