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Mr Sasson - Page 2 June 15, 1995 Original laboratory reports, including PNA results and copies of chain-of-custody forms, are enclosed with this letter in Attachment 2 •� Table 2 shows groundwater elevations measured at the three monitoring wells A potentiometric groundwater elevation map based on the groundwater measurements is provided in Figure 2 Table 2 April 1994 Groundwater Elevations Well # Casing Elevation GW Elevation MWA +5 87 ft -18 71 ft MW-5 +608 ft -19 05 ft MW-6 +688 ft -18 93 ft Groundwater Gradient Correction An error was recently discovered in the surveying of the well elevation at well MW-6 The monitoring wells were surveyed in 1991 by a State of California Licensed Land Surveyor The top of casing elevation at monitoring well MW-6 was reported to be 5 87 feet above mean sea level (msl) The corrected elevation is 6 88 feet above rnsl The documents prepared by ERM had consistently shown groundwater flow in a southeasterly direction Revised calculations of the groundwater flow direction with the corrected well casing elevation show groundwater moving in an easterly direction The revised flow direction is consistent with measurements taken in September 1989 Figure 3 shows the corrected groundwater flow direction for the • December 1994 monitoring, previously submitted to the County Site Statu5 Due to the adjusted direction of groundwater flow, Safeway is currently in the process of reviewing past data When the review has been completed, a meeting will be held between Safeway and the County, recently scheduled for June 23 After the meeting, Safeway will provide the County with a workplan designed to achieve site closure Sincerely, ERM-WEST, INC William A Spong Project Manager WAS/1218 04 Attachments Noted cc Melita Elmore (Safeway), Dennis Miller