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Ms.Tran <br /> San Joaquin County Environmental Health Department <br /> Circe K 41205 <br /> Lathrop,California <br /> January 3,2012 <br /> Page 2 <br /> Soil Bonne Samplim: and Rtlacemem of Monitgda Wells MW-1R and MW-2R <br /> Replacement wells,named MW-1R and MW-2R,will be drilled by WDC within five feet of the <br /> respective former well location. The approximate drilling locations are shown on Figure 1.Each <br /> well will be drilled to a depth of approximately 25 feet below the ground surface using a hollow- <br /> stem auger drilling rig and associated equipinea. Each well will be constructed of 2-inch <br /> diameter Schedule 40 PVC blank and skilled casing. The screened interval of each well will be <br /> from approximately 10 feet to 25 feet below the ground surface. Blank casing will extend above <br /> the slotted casing from approximate4yl0 feet to within approximately six inches below the ground <br /> surface. <br /> The annular space surrounding the stoned casing will be filled with a sand pack extending from <br /> the bottom of the boring up to a depth of approximately 8 feet below the ground surface.A <br /> hydrated bentonite seal will be placed on top of the sand pack in the annular space between <br /> approximately 4 to 8 feet below the ground surface. The remainder of the annular space will be <br /> filled with cement. A traffic-rated well box will be placed over each well and will he <br /> approximately'di-inch(nearly flush)above the grand surface.The apron of each well box will <br /> be cemented in place and dyed to match the surrounding asphah. A diagram of the proposed <br /> monitoring wells is included as Attachment A_ <br /> During the drilling program,soil samples will be collected within each boring(bfW-1R and <br /> MW-2R)from depths of approximately 9, 14,and 25 feet below the ground surface. The soil <br /> samples will be used for lithologic evaluation- The samples collected from depths of <br /> approximately 14 feet in both well locations(cast and west sides of the former tank excavation) <br /> will also serve as the sidewall samples(near the groundwater interface)for the UST removal <br /> program and will be submitted to Test America laboratory for analytical testing. The soil samples <br /> will be analyzed for Fuel Hydrocarbons using EPA method 8015 and for Volatile Organic <br /> Compounds including BTEX and fuel oxygemces(to meet the requirements of the UST removal <br /> permit). <br /> Additional Soil Boring to Con-Wige Sampling for UST Removal Prov ar m <br /> In addition to the two replacement groundwater monitoring wells,Circle K will drill one <br /> additic al soil boring to a depth of approximately 14 feet below the ground surface on the north <br /> side of the former UST basin. One and sample will be collected from the boring(at a depth of <br /> approximately 14 feet)that will serve as the northern sidewall sample for the UST removal <br /> program The approximate location of the planned boring is shown m Figure 1. The soil sample <br /> will be also be analyzed for Fuel Hydrocarbons using EPA method 8015 and for Volatile Organic <br /> Compounds including BTEX and fuel oxygenates(to meet the requirements of the UST removal <br /> permit). <br /> Report Preparation <br /> Following the completion of these activities and upon receipt of the laboratory results of the soil <br /> samples,Blaes Environmental will prepare a UST Removal and Well Replacement report to <br /> include the procedures and fmdmgs of this investigation and the activities completed for the tank <br /> removal program <br />