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Ms.Kristi Shelton Page 2 of 3 Impacted Well Destruction Groundwater monitoring wells MWl and MW2 were impacted wells and the depth to bottom in each well was monitored to insure no obstructions were present prior to over-drilling. On May 9, 2011, the well box covering MW2 was removed and the well was over-drilled to a depth of 67 feet below grade surface (bgs) using 8-inch hollow stem augers with a guide rod to keep the augers centered over the well casing. Two random soil samples were collected for soil profile purposes. EHD was present as the borehole was filled with neat cement through the augers to just below grade and covered with gravel to match the existing surface area. On May 10, 2011, the well box covering MW1 was removed and the well was over-drilled to a depth of 70 feet bgs using 10-inch hollow stem augers with a guide rod to keep the augers centered over the well casing. A composite soil sample in an area with distinct hydrocarbon odors was collected for soil profile purposes. EHD was present as the borehole was filled with neat cement through the augers to just below grade and covered with gravel to match the existing surface area. Soil derived waste generated during the destruction of these wells was placed in DOT approved 55- gallon drums pending disposal. Non-Impacted Well Destruction Groundwater monitoring wells MW3, MW4, and MW5 were not impacted wells. On May 9, 2011 the wells were destroyed by pressure grouting with neat cement grout. Neat cement grout was pumped into each well in one slow continuous operation, through a tremie pipe system, until each well was completely full. Pressure was applied at each wellhead using a pressure cap at approximately 25 pounds per square inch for five minutes forcing the grout through the well screen and into the filter-pack. The grout levels were checked for subsidence and more grout was added as necessary until the grout level in each well stabilized. Well boxes were removed and the upper 5-feet were drilled out using 8-inch hollow stem augers. The upper 4.5-feet of each boring were backfilled with neat cement grout and covered with gravel to match the existing surface area. Soil derived waste generated during the destruction of wells was placed in a DOT approved 55- gallon drums pending disposal. Soil Profile Three soil samples were collected in 6-inch brass sleeves, the ends covered with Teflon® sheets and capped, uniquely labeled, placed into an ice chest cooled to approximately 4°C, and transported to Argon Laboratories in Ceres, California (ELAP No. 2359) under chain of custody protocol for analysis. The tubes were composited into a 3:1 composite sample for landfill disposal purposes. G:\GROUNDZE\WCTOMATO\WCT-Investigation\Reports\Other\Well Destruction and Site Restoration Report V2.doc