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3.4 Water Sampling A groundwater sample was collected from VM-1 on September 11 Prior to sampling, a notch was cut l into the edge of the casing for use as a reference point for future groundwater depth measurements The well elevation was not surveyed The depth from the notch to groundwater was measured with a Solinst water level meter to the nearest 0 01 foot (Appendix C) The depth to the bottom of the well was also measured, and used to calculate Ithe volume of water in the well The well was developed by hand bailing approximately 18 gallons of water The highly turbid purge water was stored in a 55-gallon drum near the soil stockpile After purging, two 40-m1 vials and one 1-liter amber bottle were filled from the bailer and sealed The I samples were labelled and placed in a cooled ice chest and transported under chain of custody to Inchcape Testing Services The chain-of-custody form is included in Appendix B I Groundwater was again monitored and sampled on October 12 As before, the depth to groundwater was measured with a Sohnst water level meter and a disposable bailer was used to purge the standing water before a sample was collected in 40-m1 vials During purging, a Corning Checkmate meter was used to measure pH, conductivity, and temperature, and these parameters were recorded on the field data sheet(Appendix C) 4.0 RESULTS 4.1 Stratigraphy I Appendix A shows the strata that were penetrated by VM-I From the surface to a depth of 30 feet, the uppermost stratum coarsens downward from clay or silty clay to very coarse-grained sand In the upper part, the color is brown, but downward the color changes to grayish brown and gray, due to a Idecrease in oxidation and weathering Moisture content increases downward from dry to slightly damp Below 30 feet, there is an altnernating sequence of fine-grained sand, sandy silt, and silty clay Variable amounts of iron-oxide and,manganese-oxide staining result in mottled gray, orange, brown, and blue- 61ack colors to a depth of 60 feet Below this, the color is dark to very dark gray, indicating that the material has been continually below the groundwater table and is not oxidized It is also hard and Ilocally slightly cemented 4.2 Field Evidence of Contamination IHydrocarbon odors were noticed in soil samples collected at 20, 25, 30, and 35 feet The odor was strongest in the sample from 25 feet, and a maximum reading of 1585 ppm was reached on the PID No odors were noticed within or below the clay bed that lies at a depth of approximately 40 feet 3 I