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Ms.Lori Duncan October 27,2010 Page 2 of 4 Well Destruction Permitting A well destruction permit was obtained from EHD and is included in Attachment A. Ms. Lori Duncan of EHD was on site to oversee the well destruction activities. A site plan showing the location of the destroyed extraction and groundwater monitoring wells is provided as Figure 2. Well Destruction Activities Prior to well destruction activities the depth to bottom (DTB) in all site wells was measured to insure no obstructions were present in any of the wells. The eleven (11) A-Zone groundwater monitoring wells were 2-inches in diameter and varied in depth from 72 to 80 feet below ground surface (bgs); the three (3) B-Zone wells were 4-inches in diameter and varied in depth from 125 to 130 feet bgs; the two (2) C-Zone wells were 4-inches in diameter and varied in depth from 222 to 237 feet bgs; the single D-Zone well was 4-inches in diameter with a total depth of 301 feet bgs; the three (3) groundwater extraction wells were 4-inches in diameter and varied in depth from 80 to 95 feet bgs; and the two (2) vapor extraction wells were 4-inches in diameter and varied in depth from 47 to 73 feet bgs. Well construction details as well as zone designations are summarized in Table 1. On July 15 and 16, 2010, a Ground Zero Geologist, under the supervision of a California Professional Geologist, supervised V&W Drilling, Inc. [(V&W) C57 License #720904] during the destruction of groundwater monitoring wells MW5, MW7, MWS, MW10, MWll, MW14B, MW 17B, MW 18C and MW 19D and groundwater extraction well EW2 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 then applied at each wellhead using a pressure cap at approximately 20-25 pounds per square inch (psi) for three minutes forcing the grout through the well screen and into the filter-pack. The grout levels were then checked for subsidence and more grout was added as necessary until the grout level in each well stabilized. After the wells were grouted, the well monuments and boxes were removed and the upper five feet of the 2-inch diameter wells were overdrilled with 8-inch diameter hollow stem augers and the upper five feet of the 4-inch diameter wells were overdrilled with 10-inch diameter hollow stem augers. The resulting annulus was then backfilled with neat cement grout to approximately 3-feet below grade and the soil cuttings were used to backfill to ground surface. On October 4, 5, 6 and 7, 2010, a Ground Zero Geologist supervised V&W during the destruction of groundwater monitoring wells MW4, MW6, MW9B, MW12, MW13C, MW15 and MW16 and vapor extraction well VW2 by pressure grouting with neat cement grout. The wells were destroyed using the protocol described above. Wells located in the parking lot were backfilled with neat cement to ground surface and completed to match the surrounding surface. G:IGROUNDZE%TULEBERG\Reports\Other%Well Dest Rpt.doc