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1 VOGUE CLEANERS WELL ABANDONMENT REPORT 2 3 1). PURPOSE 4 The Vogue Cleaners site investigation has been completed and the well abandonment plan has been 5 executed. The purpose of this report is to describe the as built condition of closure. The Leaded 6 Gasoline Tank and the Stoddard Solvent Tank were removed in 1996. The soil under both tanks was 7 found to contain hydrocarbon contamination which launchEd an investigation concluding with 20 8 groundwater monitoring wells, 8 Cone Penetration samples and two soil vapor collection probes. 9 10 The limit of the plume has been defined and the natural deE radation trend lines illustrate declining 11 concentrations. No further action on this site is warranted nd the remaining wells and soil vapor 12 probes were abandoned on 9/29/11 through 10/20/11. 13 14 2).SCOPE OF WORK 15 Exhibit B contains the As-Built Well Abandonment Limit Schedule. This chart illustrates as-built 16 installation limits and the as-built abandonment limits. The limits were previously reviewed and 17 approved by EHD in the work plan "VOGUE CLEANERS WELL ABANDONMENT PLAN REVISED 7/13/11". 18 19 3). GROUT 20 The grout was a slurry of Portland cement and potable water. One 94#sack of Type 1/II Portland 21 Cement was mixed with 5-10 gallons of water to make the grout. 22 23 4). EXECUTION OF PRESSURE GROUTING 24 Prior to removing the well boxes,the 2"casings of monitori g wells MW-75, MW-8S and MW-11S were 25 pressure grouted to hold 25psi of grout pressure for at least 10minutes. A mushroom cap was 26 excavated by hand to achieve 36" of depth and at least 20" liameter. The diameter was to be 12" larger 27 than the original 8" bore. The 2" casing was cut off at 30" d ep to provide 6"of protrusion into the 28 mushroom cap. The excavation was filled with grout to a d pth of 18" or higher to provide at least 12" 29 of grout over the 2"casing protrusion. The settled surface f the grout was verified to be at 18" depth 30 or higher prior to backfilling and finishing the surface. 31 32 5). EXECUTION OF CONTENT REMOVAL 33 The contents of the single wells were removed with an 8" hollow stem auger with a 1.75"x30"stinger 34 protruding from the end plug to follow the well casing clown to tip. Removal of the contents of all single 35 wells was successful except for MW-10D. Prior to reaching the water table at 37'the cuttings from 30' 36 deep were clean soils suggesting the auger had veered of the grout column. The auger was advanced to 37 35' to confirm and the decision was made to grout the well 3t 35'. There is no reason to drill a hole in 38 soil just to fill it with grout. 39 40 Removal of the contents of nested monitoring wells MW-2 &D and MW-5S&D with a 15" auger was 41 successful. 42 43 Removal of the contents of nested monitoring well MW-4S&D with a 15" auger was successful, but the 44 withdrawal of the auger was not. The auger made tip at 75',was grouted and 40' of auger was 45 removed. After the second grouting the augers seized and could not be turned or lifted. The bolts 46 pining the augers together failed negating any attempt to remove the augers. 30' of augers plus the 47 tooth collar was abandoned in place with grout between depths 3'to 34' below ground surface.