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(Figures 3 and 4), concentrations of TPH-as-Gasoline in excess of 10,000 mg/kg are likely present between approximately 13 and 24 feet bgs directly beneath the former LISTS Concentrations of TPH-as-Gasoline in excess of 100 mg/kg likely extend to a depth of approximately 40 feet bgs Minor concentrations of TPH-as-Gasoline (2 2 mg/kg) and benzene (0 34 mg/kg) were detected at a maximum depth of 65 feet bgs in MW-3 Minor concentrations of TPH-as-Gasoline ranging from 1 1 mg/kg to 2 2 mg/kg were also detected in sod between 56 and 62 feet bgs in MW-1, VW-2 and MW-3, likely resulting from the downgradient spreading of the gasoline hydrocarbons on the historic groundwater table Laterally, the majority of the gasoline hydrocarbon mass is confined to the footprint of the former USTs and soils immediately north Since the UST system was situated immediately east of the mausoleum budding, the extent of impacted soil is not defined to the west Concentrations of TPH-as-Gasoline in excess of 10,000 mg/kg were detected only in one soil sample from MW-1, collected directly beneath the former USTs Concentrations of TPH-as-Gasoline in excess of 1,000 mg/kg were also detected in SB-2 and VW-3, approximately 20 feet north of the former USTs Due to the lateral spreading of gasoline hydrocarbons on the historic water table, minor concentrations of TPH-as-Gasoline and benzene were detected in sod approximately 40 north and 30 feet east of the former USTs (Figure 6) 3 2 2 Groundwater Impact To date, groundwater has been sampled from seven groundwater monitoring wells (MW-1 through MW-7) and two deep vapor extraction wells (VW-1D and VW-2D) The construction specifications for each of these wells and the four shallow vapor extraction wells (VW-1 S, VW- 2S, VW-3 and VW-4) are summarized in Table 3 Until the summer of 1996, groundwater was only sampled from the five original groundwater monitoring wells The highest concentration of gasoline hydrocarbons detected in groundwater up until this time was 1,100 µg11 of TPH-as-Gasoline and 160 µg/I of benzene from MW-3 However, as the Hydrograph vs Concentration Diagram for MW-3 illustrates (Figure 7), TPH- as-Gasoline was not detected in this well once the groundwater level had risen above the top of the screen interval In September 1996, quarterly monitoring of the five original groundwater monitoring wells was discontinued Instead, groundwater was sampled from the two deep vapor extraction wells (VW- 1 D and VW-2D) with screen intervals spanning the groundwater table elevation Groundwater sampled from VW-213 contained 11,000 µg/I of TPH-as-Gasoline and 1,300 µg/l of benzene, thus substantiating the theory that groundwater samples collected from wells with groundwater 10