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S E C 0 R
<br /> 3.0 CURRENT ASSESSMENT ACTIVITIES AND RESULTS
<br /> Between February 9 and February 18, 2005, SECOR supervised the drilling of two deep
<br /> direct push soil borings (DGP-1 and DGP-2) to depths ranging from 70 to 75 feet below
<br /> ground surface (bgs), and three shallow groundwater monitoring wells (MW-17, MW-1$,
<br /> and MW-19) to 25 feet bgs. Soil samples were collected continuously from borings
<br /> ' DGP-1 and DGP-2, and selected soil samples were submitted for laboratory analysis_ -.
<br /> Hydropunch groundwater samples were collected at depths of 52 and 72 feet bgs in
<br /> boring DGP-1, and at depths of 46 and 70 feet bgs in boring DGP-2. No soil samples
<br /> were collected from wells MW-17, MW-18, and MW-19 due to their proximity to previous
<br /> geoprobe boring locations. Soil samples were analyzed for TPHg, BTEX, fuel
<br /> oxygenates (MtBE, EtBE, TAME, TBA, DIPS, EDB, 1,2-DCA and ethanol) by EPA
<br /> ' Method 82606, and total lead by EPA Method 6010B. Groundwater samples were a
<br /> analyzed for TPHg, BTEX, and fuel oxygenates by EPA Method 8260B, and dissolved
<br /> lead by EPA Method 60108. Soil and groundwater analytical results are presented in
<br /> Tables 4 and 5.
<br /> The soil sample from boring DGP-1 at 15 contained TPHg ethylbenzene,(benzene total xylenes,
<br /> MtBE and TBA at concentrations of 7.7 ppb, 0.035 ppb, 0.064 ppb, 0.021 ppb an0.013
<br /> ppb, respectively. The soil sample from boring DGP-1 at 30 feet contained MtBE at a
<br /> concentration of 0.0066 ppb. The soil sample from boring DGP-2 at 14 feet contained riA,
<br /> TPHg, benzene, ethylbenzene, and total xylenes at concentrations of 11 ppb, 0.044
<br /> ppb, 0.058 ppb, and 0.25 ppb, respectively. Total lead was reported in each of the
<br /> samples form boring DGP-1 and DPG-2 at concentrations ranging from 1.4 ppb to 80
<br /> 1 ppb'
<br /> The four hydropunch groundwater samples from borings DGP-1 and DGP-2 contained
<br /> TPHg, ethylbenzene, and total xylenes at concentrations of up to 1,400 ppb, 31 ppb,
<br /> 100 ppb, respectively. Benzene and toluene were detected in three of the four samples fiM
<br /> at maximum concentrations of 0.76 b and 1.3 p
<br /> pp ppb, respectively. MtBE was detected
<br /> in the samples from DGP-1 at a maximum concentration of 29 ppb at 52 feet. TBA was
<br /> detected in this sample at 5.4 ppb.
<br /> Wells MW-17, MW-18, and MW-19 were developed and sampled on March 11, 2005.
<br />' TPHg was reported in well MW-17 at a concentration of 87 ppb. Other hydrocarbons
<br /> constituents were reported as not detected at or above laboratory reporting limits.
<br /> Soil stratigraphy encountered in boring DGP-1 generally consisted of sand and silts at
<br /> depths of 0.5-10 feet, 20-28 feet, 32-38, and 49-75 feet, and clay and site from 10-20
<br /> feet, 28-32 and 38-49 feet. Soil stratigraphy encountered in boring DGP-2 generally
<br /> consisted of sand at depth of 0.5-10 feet, 15-19 feet, and 54-70 feet. Clay layers were
<br /> encountered between 10-15 feet, 19-46 feet and 48-54 feet. Hydropunch groundwater
<br /> sample DGP-1@52' was collected in a silty sand layer and DGP-1 @72' was collected in
<br /> r a well graded sand layer. Hydropunch groundwater samples DGP-2@46' was collected
<br /> f in a fat clay layer and DGP-2@70' was collected in a poorly graded sand layer.
<br /> C 1205 SCM.doc
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