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r <br /> other will be used to withdraw the sample. All equipment <br /> including the bailers, and bailing cord, and the water depth <br /> r measuring devise must be decontaminated prior to entering any <br /> well. They will be decontaminated by washing with Tri--sodium <br /> phosphate detergent and water and thoroughly rinsing them with <br /> clean water. <br /> The depth to groundwater will be measured from the highest point <br /> r on the top of the casing to the surface of the water table. The <br /> devise used will be an electric conductivity devise which trips <br /> a red light and a buzzer when the probe touches water. A <br /> minimum of three measurements will be made at each well, the <br /> final reading will be noted after 2 or more readings do not vary <br /> by more than 0 .03 feet. <br /> r <br /> once the depth to water is known the tape and probe will be <br /> withdrawn from the well and thoroughly dried. A small amount of <br /> water paste will be placed on the axis of the probe and the <br /> probe will be lowered to the water table. Care will be taken to <br /> r not allow the probe to descend into the water below the contact <br /> point. Then the probe will be withdrawn rapidly and inspected <br /> for signs of fluid above the contact point. If fluid is noted <br /> the is will be smelled to verify it is fuel , then the thickness <br /> of the fuel will be noted on the measuring log. <br /> Water samples will be obtained as follows: <br /> A) First one full well volume of water will be withdrawn from <br /> the well ; <br /> B) The parameters of Ph, Conductivity, and Temperature will be <br /> measured; <br /> C) A 2nd and 3rd well volume of water will be withdrawn and the <br /> parameters remeasured, if the results vary by more than 10% then <br /> step C is repeated; <br /> 1 D) The well is allowed to recover to 80% of its original volume <br /> or 2 hours have passed then a sample will be withdrawn and <br /> placed in its appropriate container. <br /> Purged water will be placed in a drum sealed and left at the <br /> site until its hazardous condition is assessed. <br /> 1 <br /> Each well site will be surveyed to within 0.5 Ft. horizontally <br /> and to within 0.01 Ft. vertically. The elevation to the top of <br /> the casing in each well will be measured with a spirit level and <br /> surveyors rod. The leveling will take place at least 24 hours <br /> after the casing seal and traffic box have been set. <br /> 1 <br /> Water samples will be taken from the water at or near the <br /> surface of the water table, unless otherwise indicated. Water <br /> Page 18 <br /> 1 <br />