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t 15 June 2009 AGE-NC Project No.05-1306 Page 12 of 33 Monitoring well MW-2 was destroyed on 16 August 2005 as part of over-excavation activities to a L remove hydrocarbon-impacted soil related to a former UST at the site.Over-excavation of the former diesel fuel UST excavation was conducted between 05 and 29 September 2005,and monitoring well MW-2R (replacement well for well MW-2) was installed on 09 November 2005. The work was performed in accordance with the AGE-prepared Soil Remediation Work Plan -Former USTArea, j dated 20 June 2005, and approved by EHD on 07 July 2005. 5.1. MONITORING WELL DESTRUCTION On 16 August 2005, in preparation for over-excavation of petroleum hydrocarbon-impacted soil at the site,monitoring well MW-2 was over-drilled to total depth.To facilitate excavation,the well was backfilled to surface grade with Type 1111 Portland cement. 5.2. SOIL OVER-EXCAVATION Prior to over-excavation,the proposed over-excavation pit was shored with interlocking sheet piling to prevent the cave-ir of and provide stability to the over-excavation pit walls. Soil was excavated to 28 feet bgs. 5.2.1 Soil Over-excavation and Shoring On 05 September 2005,a shoring trench 2-foot wide by 3-foot deep on the perimeter of the proposed over-excavation was excavated utilizing a backhoe by Valued Engineering of Stockton, California (Valued). On 12 to 14 September 2005, installation of shoring was performed by Cooper Crane& Rigging, Incorporated of Novato, California (Cooper). Cooper hammered in 45-foot lengths of interlocking sheet piling with a vibratory driver/extractor suspended from a crane and operated from the surface to approximately42 feet bgs.Cooper reinforced the shoring by welding steel beamwalers and associated structural supports to the steel sheet piling within the over-excavation pit at approximately 12 feet bgs. On 16 to 21 September 2005,Valued Engineering excavated the soil to approximately 28 feet.Clean overburden soil was expected to 10 feet bgs, but during over-excavation activities, petroleum hydrocarbon-impacted soil was encountered at approximately 5 feet bgs.Impacted soil was observed to extend from approximately 5 feet bgs to the floor of the over excavation. AGE personnel screened over-excavated material through field observations consisting of odor and �., visual examination.Impacted soil was stockpiled separately from non-impacted soil(soil excavated Advanced GeoEnvironmental,Inc.