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I 4.0 CONCLUSIONS ' Blaes Environmental conducted two groundwater monitoring events at U-Haul facility #709-50 in December 2000 and March 2001 The results of these groundwater monitoring events were similar to ' those of the previous sampling event conducted in September 2000 In general, groundwater levels have risen approximately six feet from September 2000 to March 2001 Groundwater levels rose approximately 1 5 feet between the December and March monitoring events Despite the rise in groundwater levels, the upper"A" well casings did not contain water in December 2000 or March 2001 � Based on the groundwater level measured at the middle "B" well casings, the groundwater surface maps ' for December and March did not reveal a dominant groundwater gradient for the site The groundwater surface in the area is relatively flat and the groundwater flow patterns at the site vary between monitoring events Analytical results of groundwater samples collected in December 2000 indicated the presence of hydrocarbons in groundwater across the site With exception to results of samples from well MW-413, the . drop in groundwater levels from the depth range of the upper"A"well casings to the middle "B" casings has been accompanied with an increase in detectable hydrocarbon concentrations in samples from the middle "B" well casings Analytical results of the December 2000 sampling event indicated that the extent of hydrocarbons at the groundwater surface have spread over the entire site (Figure 4) Results of samples collected from the lower well casings in December 2000 indicated that the extent of hydrocarbons was much less widespread than in the middle well casings Samples from wells MW-I, I MW-2, MW-3, MW-5, and MW-8, which cover the northern half of the site, did not contain detectable concentrations of TPHg or benzene(Figure 5) IAnalytical results of groundwater samples collected in March 2001 from the middle "B" and lower well casings both indicated the presence of hydrocarbons in groundwater across the site Results of samples collected from the middle "B" well casings revealed similar results to those of the December 2000 sampling event In this case and with previous results, the main portion of the hydrocarbon plume (with ITPHg concentrations greater than 1,000 µg/L) extends across the central portion of the site from east I (MW-4B) to west (MW-6B) Results of samples collected from the lower well casings in March 2001 1 07/10,01 Blaes Project#002-70950-02 I S bjm C 1BLAESIU-Hau1170950170950r101 doe I