Laserfiche WebLink
s/ ! <br /> Mr. Ross Atkinson <br /> Page 2 <br /> rig. The location of the boring corresponded to previous hand auger boring location "C-4.5" <br /> (Figure 2). Soil samples were collected using a split-spoon sampler with brass liners at five-foot <br /> intervals from 15 feet to 45 feet bgs. Upon completion, the boring was backfilled to the surface <br /> with cement grout. <br /> Samples were transported under chain of custody to State-certified A & L Western Agricultural <br /> Laboratories (FLAP No. 1657) for analysis. The samples were extracted by the DI WET <br /> procedure and the extracts analyzed for TDS, chloride and sodium using EPA Method 160.1, SM <br /> 4500 and EPA Method 273.1, respectively. <br /> Observations and Analytical Results: <br /> Soils encountered in the boring consisted of interbedded sands, silts and clays to total depth. Very <br /> dense sand and silt (possible hardpan) was observed in the samples collected at 15 feet and 20 feet <br /> bgs. Groundwater was encountered at a depth of 44 feet bgs. A boring log is included in <br /> Attachment A. <br /> TDS in the sample extracts ranged from 84 to 350 mg/1 and averaged 176 mg/l. Chloride ranged <br /> from 12 to 18 mg/l and averaged 15 mg/l. Sodium ranged from 7.7 to 13.1 mg/l and averaged <br /> 10.7 mg/l. <br /> At boring location C-4.5/DBI a vertical profile of generally increasing analyte concentrations to a <br /> depth of approximately 10 feet was observed. Between the depths of approximately 10 and 20 feet <br /> concentrations were at the highest levels; concentrations decreased below this depth to the water <br /> table. Figure 3 depicts the concentrations with depth at the boring location. Analytical data are <br /> summarized in Table 1. Laboratory data sheets and chain of custody documentation are included in <br /> Attachment B. <br /> Conclusions: <br /> The results of this investigation confirm the conclusion that soils within Pond 2 are not significantly <br /> elevated in salinity and do not pose a threat to groundwater quality. <br /> The absolute concentrations of TDS, choride and sodium in none of the sample extracts exceeded <br /> drinking water standards. <br /> 8"damBWblryl <br />