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BlaeS Envrro"MentalManagemenr Inc 002-70950-03 U-Haul#709-50 Work Plan 11/8/01 The lateral extent of hydrocarbons in soil was better defined with analysis of soil samples collected from boreholes DP-3 and DP-6 Borehole DP-3 apparently defines the northern lateral extent of hydrocarbons in N ,� soil with detectable concentrations of TPHg less than or equal to 1 0 mg/Kg and detectable benzene concentrations less than 0 72 mg/Kg (Figure 4) Soil from this borehole did not contain detectable concentrations of hydrocarbons at depths of 70, 100, and 110 feet bgs(Table 2) Borehole DP-6 appears to define the western lateral extent of hydrocarbons in soil with detectable W concentrations near detection limits and non-detectable results at depths of 60, 90, and 120 feet bgs The southeastern extent of hydrocarbons apparently extends off site The limit of impacted soil southeast of the source area was inferred using the distance between DP-6 and the source area Southeast of the source area, analytical results of soil from DP-4 and MWAa defined the degree of impacted soil near the eastern property E boundary The vertical extent of hydrocarbons in soil was better defined with analytical results of soil samples from boreholes DP-2, DP-3, DP-4 and DP-6 The soil sample from DP-2 at 120 feet bgs consisted of sandy clay and did not contain detectable concentrations of hydrocarbons This was the deepest sample collected from DP-2 Soil samples collected from DP-3 at approximately 100 and 110 feet bgs consisted of silty sand and sand Both of these samples from DP-3 did not contain detectable concentrations of hydrocarbons (Table 2) 2 6 PREVIOUS GROUNDWATER MONITORING RESULTS Recent work performed by Blaes Environmental has included quarterly groundwater monitoring The most recent groundwater monitoring events were conducted in July and September 2001 Both groundwater monitoring events included groundwater sample collection from all wells that contained water The list of well casings available for groundwater monitoring and sampling is provided in Table 1 During both sampling events, groundwater samples were not collected from any of the upper "A" well casings due to deeper groundwater levels Previous groundwater level measurements indicated a decrease in water levels of approximately 5 to 6 feet from July to September 2001 Groundwater level measurements recorded in July 2001 ranged from 49 94 feet below top of casing (BTOC) at MW-7 to 53 25 feet BTOC at MW-6 Groundwater level measurements recorded in September 2001 ranged from 55 88 feet BTOC at MW-7 to 59 04 feet BTOC at MW-6 No free-phase hydrocarbons were observed during collection of groundwater level 6