Laserfiche WebLink
a <br /> ii <br /> I <br /> 3.13 GROUNDWATER SAMPLES <br /> _ Figure 3-1 shows the location of the groundwater monitoring well. The well will be <br /> completed directly beneath the former location of the northern tank. A bail test will be <br /> performed to provide data on aquifer transmissivity, and two groundwater samples will <br /> be collected from the monitoring well. <br /> =) In order to prevent boring through contaminated soil and still obtain a e.oundwater <br /> 1.< sample directly beneath the tank pit, a slant boring is proposed for Monitoring <br /> Well.MW-DIS-1: A schematic of this slanted monitoring well is shown on Figure 3-2. <br /> r� Monitoring well installation procedures and well design specifications are described in <br /> I Section 4.3. <br /> Analytical results of the soil samples taken from and below the former t?nk pit will be <br /> reviewed before the monitoirng well is drilled. Ifthe`iesults inclii•?te;that the soil <br /> gr <br /> contamination level is-too low to cause cross contamination 'of `'oundwater during <br /> drilling,.then Monitoring Weil'MW-DIS-1 will be drilled vertically through the former <br /> t' <br /> location of the northernmost tank. <br /> 3.2 SAMPLING METHODOLOGIES <br /> .3.2.1 SOIL-GAS SAMPLING <br /> t., Soil-gas sampling probes will be inserted between depths of 7 and 20 feet below grade. <br /> All analyses of the samples will be performed onsite using a mobile laboratory <br /> equipped with a gas chromatograph, <br /> 3.2.2 SOIL SAMPLING <br /> Boreholes will be drilled using a hollow-stem continuous-flight augering method. The <br /> auger size to be used is 8-inch outside diameter (OD). Samples will be collected at 5- <br /> foot.vertical intervals using a split-spoon sampler lined with brass sleeves. Soil <br /> r, sampling procedures are presented in detail in Section 4.3. <br /> The samples from each boring will be submitted for chemical analysis as described in <br /> L: Section 3.3. Each borehole, upon the completion of sampling, will be filled to the sur- <br /> face with grout. <br /> After sampling, each borehole will be filled to othe surface with grout." <br /> sF031604MP07.5 1 3-3 <br /> y-ti <br />