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ler Previously MW No 3 was suspect as the lid had been removed and the casing ' plug was not in place at the March 26th sampling It may be noted that the previous quarterly readings of MW No 3 were as low as 0 19 mg/Itr in September t 2003, 0 39 mglltr in December 2003 and the suspect 0 58 mg/ltr in March 2004 Contamination levels in this well were 0 31 during this quarterly sampling (December 2004) In an effort to establish a "clean line" further out from the source, CPT bonngs were carried out in November 2003 followed by the second round reported herewith On ' May 28, 2004, nine new holes were pushed using a CPT rig to ground water to sample outlying groundwater to determine if the new sampling points were beyond the underground hydrocarbon plume Results varied between <0 062 ' mglltr and 0 150 mglltr at the westernmost point 55 FT north of MW 3 Groundwater contamination between 50 to 55 FT bgs exists Excepting the just ' noted 0150 mglitr north of MW 3, diminishing or non-detect hydrocarbon contamination was found north of the site's property during the May CPT borings While a ND defining the leading edge was not found, most recent CPT borings ' located further out from the source were less than 0 078 mglltr The original underground storage tanks (USTs) suspected source has been removed The closest operating offsite down gradient well is at least 600 FT away Residual Nshallow soil contamination, possibly contributing to the ground water contamination has been identified and removal of a portion not covered by structures may be anticipated ' Removal of shallow contaminated soil wasro osed in the 12 August 2004 work P P g ' plan for Fall 2004 However, upon discussion with your agency WOS agreed to further characterization in the field north of the site CPT and hydropunch methodology will be employed in an attempt to define the plume's leading edge ' and characterize any threat posed to neighboring property shallow domestic wells While we were hopeful to perform the CPT work this fall it could not be started prior the beginning of the wet season Work has been postponed until ' the field area has dried enough to construct access to the anticipated boring locations CPT work is tentatively anticipated in May 2005 Trenching, by WOS, in the area between MW No 2 (east fence line and the concrete block wall t secondary containment area between MW's No 1 and No 6 in November 2004 revealed soil contamination The findings are discussed in the attached report and its ATTACHMENT 8, FIELD INVESTIGATION SHALLOW SOIL, 22 ' November 2004 Access to this area is important to WOS for material handling at the Acampo facility A summary of all ground water sampling events is included REFERENCE ATTACHMENT 2, SUMMARY OF LAB RESULTS included with the report