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Three of the five soil samples contained slightly elevated concentrations of total <br /> . g Y lead (up to 91 <br /> ppm) To further evaluate these lead concentrations, the laboratory combined the five samples <br /> into one composite and re-analyzed the sample for total lead and soluble lead The results <br /> indicated that the lead content in the sod was below hazardous concentrations outlined in Title 22 <br /> of the California Code of Regulations <br /> On November 22, 1999, PHS/EHD approved the transfer of the remediated sod to the City of <br /> Manteca Police Confidence Course On December 3, 1999, Bob Evans Trucking loaded and <br /> transported the remediated sod to the Police Confidence Course in 64 loads, using ten-wheel <br /> trucks According to Bob Evans Trucking, each truck was loaded with approximately 8 cubic <br /> yards of sod, for a total soil volume of 512 cubic yards transported <br /> ' 1.2 4 Preliminary Investigation and Evaluation <br /> ' On September 2, 8, and 9, 1999, in order to evaluate the extent of impacted soil and/or <br /> groundwater and to identify any sensitive receptors in the site vicinity, Ramage Environmental <br /> supervised the drilling of 11 on-site Geoprobe® soil borings (Figure 2) Sods observed in the 11 <br /> sod borings consisted of massive sand intervals interrupted by alternating thinly-bedded <br /> sequences of clay, silt and fine sand mixtures Groundwater levels measured in each of the soil <br /> borings ranged from 17 5 to 19 0 feet bgs <br /> The results of the soil sample analyses are summarized in Table 2 Vertically, the extent of <br /> impacted sod beneath the site was defined in six of the 11 soil borings Laterally, the majority of <br /> the petroleum hydrocarbon mass in soil is concentrated at approximately 25 feet bgs The <br /> concentrations of MTBE detected in the deeper sod samples are present in the northeastern and <br /> northern portions of the site <br /> The results of the groundwater sample analyses are summarized in Table 3 The groundwater <br /> samples from all 11 of the soil borings contained a detectable concentration of at least one of the <br /> ' compounds analyzed The highest concentrations of TPH-as-gasoline (62,000 µgll) and benzene <br /> (230 µg11) were detected in SB-6, north of the dispensers The highest concentrations of MTBE <br /> (9,600 µg/1), TBA (180 jig/1), tertiary amyl methyl ether (TAME) (14 µg11) and di-isopropyl ether <br /> (DI PE) (3 8 p.g/l) were detected in SB-10, northeast of the UST excavation The lateral extent of <br /> impacted groundwater is undefined to the west, north and east of the site Only the groundwater <br /> sample collected from the on-site domestic well was free of detectable concentrations of TPH-as- <br /> gasoline, BTEX, and/or oxygenates <br /> 7 <br />