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13 2 Soil Contamination <br /> Findings by Barber's study indicated non-detect levels of BTEX hydrocarbons in soil at <br /> ' boreholes C-1 and C-3 (excepting very low levels ethylbenzene and xylene (less than 0 015 <br /> mg/kg reported in C-3) as well as only trace amounts of ethylbenzene and xylene (less than <br /> 0 065 mg/kg reported in C-517) Contamination with heavier fractions (purgeable C6- <br /> C12) was found in soil between 25 and 40 FT bgs in boreholes C-2 and C-4/6, ranging <br /> ' upwards to 15,500 mg/kg and at 25 FT bgs in borehole C-517. A scaled and updated site <br /> map with boring locations identified is attached as Figure 5 A compilation of all findings <br /> may be found in Table 1, "Summary of Laboratory Findings" <br /> Non-detect levels were found in tested sod samples from MW No 1 albeit samples were <br /> ' only tested below 35 FT bgs An updated graphical representation of the findings may be <br /> found in the <br /> ' 1.3.3 Groundwater <br /> Groundwater was sampled when encountered in the boreholes and from the monitoring well <br /> on January 10 and March 30, 2001 While BTEX was only above 0 500 ug/L in Borehole C- <br /> 416, fable hydrocarbons were identified in groundZeter samples at boreholes C-1, C-2- <br /> C-3 - - <br /> 1. <br /> ' Source of contamination was not visibly apparent at time of bonngs but was not expected <br /> Earlier removal of underground storage tanks in the vicinity of the installed monitoring well and <br /> ' the earlier identification of contamination of heavier fractions between the 20 and 30 FT <br /> depths indicate probable leakage from the USTs <br /> The groundwater gradient sloped at 0 0092 and between December 2000 and April 2001 its <br /> direction had vaned by several degrees about N 5 deg E Historically, the ground- water <br /> ' flows to the north in this area This was venfied with measurements of the 50 FT deep <br /> groundwater surface at several surrounding wells The permeable, somewhat homogeneous <br /> ' sods and very little encountered ("perched") water supports the data gleaned from existing <br /> wells' relevance Groundwater measurements were also taken in the existing "active' <br /> domestic well near the southwest corner of the Acampo Plant Site They were discounted <br /> due to insufficient recovery period after pumping before standing water level stabilized <br /> 1-6 <br />