Laserfiche WebLink
6.0 DATA EVALUATION <br /> This section presents an evaluation of the data gathered during the Phase II site assessment <br /> in terms of site hydrostratigraphy, soil quality, and ground water quality <br /> 61 HYDROSTRATIGRAPHY <br /> Soils encountered at the site consisted of interbedded sand, silty sand, and clay The upper <br /> 8 to 14 feet of the soil profile typically consisted of yellowish-brown, fine- to medium- <br /> grained sand and sandy silt. The underlying soils typically consisted of interbedded grayish <br /> brown clay and yellowish brown fine- to medium-grained sand Ground water was <br /> encountered in Borings B-2, B-3, and B-6 at a depth of about 28 feet below grade Water <br /> stabilized within the temporary casings at about 25 feet below grade The water-yielding <br /> strata in Borings B-3 and B-6 consisted of fine- to coarse-grained sand. The 26- and 31-foot <br /> samples collected from Borings B-2 consisted of very moist clay However, due to the <br /> significant amount of water yielded, it is inferred that a sand lens may have been present <br /> within the clay stratum Edited copies of the field boring logs for each of the eight borings <br /> are included in Appendix D. <br /> 6 2 SOIL QUALITY <br /> The results of the soil sample analyses, summarized in Table 1, indicate elevated <br /> concentrations of TPH-g and BTEX in certain soil samples collected from Borings B-1, B-2, <br /> and B-3. The highest detected concentrations were in the 16-foot sample from Boring B-1 <br /> and in the 31-foot samples from Borings B-2 and B-3 It is noted that Borings B-1 and B-2 <br /> were drilled in the suspected former location of the three gasoline tanks (Figure 2) The <br /> presence of high TPH-g/BTEX concentrations at the 16-foot depth in Boring B-1 suggests <br /> that this boring is within or very near the footprint of the former gasoline tanks The <br /> samples collected from Borings B-2 and B-3 at a depth of 31 feet were saturated with water <br /> The elevated TPH-g and BTEX concentrations detected in these samples suggest that <br /> hydrocarbon contamination may have migrated along the soil/ground water interface As <br /> shown in Table 1, BTEX concentrations in soil are quite low when compared to <br /> 6-1 <br /> 03-MICYSTEM <br /> Consultants, Inc <br />