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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 mglltr in September 2003, 0 39 mglltr in December 2003 and the suspect 0 58 mglltr in March 2004 tContamination levels in this well were 0 30 during this quarterly sampling (September 2004) In an effort to establish a "clean line" further out from the source, CPT bonngs were carred 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 dust noted 0150 mglltr 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 soil contamination possibly contributing to the contamination has been identified and removal of a portion not covered by structures may be anticipated upon acceptance of the work plan submitted concurrently with this report A summary of all ground water sampling events is included REFERENCE ATTACHMENT 2, SUMMARY OF LAB RESULTS included with the report A copy of Del-Tech Geotechnical Support Services field 17 September 2004 monitoring report is attached, as ATTACHMENT 8 Please contact me at 530 823-215 knave any questions on findings or P ( ) recommendations contained in this '' f � Sincerely, . } 0 ^/ 3 � rx Daniel K Barber P E D K Barber P E & Associates �',T n �- •- . �a Attached Sep 17�h MW Sampling findings - Cc 1 copy via FedEx to CVRWQCB 1 Cc Client WOS 3 1