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Water Sampling Procedures: i ' The equipment used to withdraw water from the well will be a PVC or stainless steel bailer or a PVC electric pump and hose. At the samplers option, he may purge the well with an electric pump. ' All equipment including the bailers, bailing cord, water depth measuring devise and the pump and electric lines and hose must be decontaminated prior to entering any well . They will be decontaminated by washing with Tri-sodium phosphate detergent and ' water and thoroughly rinsing them with clean water. The well will be purged and a water sample will be taken immediately after purging. The depth to groundwater will be measured from the highest point on the top of the casing to the surface of the water table. The ' devise used will be an electric conductivity devise which traps a red light and a buzzer when the probe touches water. A minimum of three measurements will be made at each well, the final reading will be noted after 2 or more readings do not vary by more than 0.01 feet. The total depth of the well will also be measured. This information along with water parameters mentioned later will be entered onto the sampling sheet. The well volume will be calculated according to the formula supplied. The presence of floating free product will be checked by noting the depth of the water and marking that level on the probe wire. The probe and wire will be withdrawn from the well and dried. Liquid paste or chalk will be placed on the probe and up the side of the wire for 2 feet (could be higher depending on the depth of the plume) . The probe is then carefully lowered into the well so that the probe just touches the water table, care will be taken not to lower the probe below the water table. Once the probe has buzzed the water table the probe is withdrawn quickly from the well and the liquid level above the water level point on the probe is measured. This liquid level is the floating product thickness and will be recorded on the sampling sheet. Water samples will be obtained as follows: A) First, one full well volume of water will be withdrawn from the well; B) The parameters of pH, conductivity or resistivity, and temperature will be measured. The color, odor and presence of a sheen of the purged water will be noted; C) A '2nd and 3rd well volume of water will be withdrawn and the parameters remeasured, if the results vary by more than 10% then step C as repeated; D) The well will be allowed to recover to 80% of its original volume or 2 hours have passed then a sample will be withdrawn and placed in a the appropriate sample bottle supplied by Sherwood Laboratories of Hilmar California. Sherwood Labs supplies the