ARCHIVED REPORTS PR0544462 - Laserfiche WebLink

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On January 2, 1991, two eight-inch soil borings were drilled and completed as groundwater monitoring wells (MW2 and MW3) by Spectrum Exploration (C57 #512268) using a hollow stem auger drill ng The wells, completed at a depth of approximately 23 feet below grade, were constructed of two-inch diameter F480 threaded PVC casing and 0 010 inch slot screen The locations of the wells are shown on Figure 2 Capillary fringe soil samples, collected at six feet below grade, were submitted for laboratory analysis for BTEX and T'PHd No constituents were detected in the samples (Table 1) Beginning January 4, 1991 until January 1, 1994, wells MW2 and MW3 were monitored and sampled on a quarterly basis Water samples were analyzed for BTEX, TPH& and TPHd by appropriate EPA and DHS methodologies During the eleven rounds of groundwater sampling from well MW2 and MW3, petroleum hydrocarbons have been detected only twice In July 1991, trace levels of BTEX and TPHg were reported in the sample collected from downgradient well MW2 along with traces of ethylbenzene and xylenes in the sample collected from upgradient well MW3 In July 1992, the sample from well MW2 was reported to contain 18 parts per billion (ppb) xylenes along with 120 ppb TPHg Analytical results for groundwater are included as Table 2 PROPOSED SCOPE OF WORK Smith Environmental proposes the following scope of work to evaluate potential residual soil contamination at the subject site Advance Four Soil Borings, Soil[ Sample Collection and Analysis Smith Environmental will supervise the advancement of four soil borings to a depth of approximately 10 feet below the ground surface or to the first encountered groundwater at the locations shown on Figure 2 Sample collection will be conducted by a State-licensed (C57) drilling company using direct push methodology Samples will be collected using the Geoprobe 5400 Soil Probe Unit, a dual-rod sampling technique which will enable collection of undisturbed soil samples at the desired depths Soil samples will be logged by a field geologist and screened every five feet with a photo ionization detection meter (PID) Two samples per boring will be submitted to a State-certified laboratory for analysis of BTEX, TPHg, and TPHd utilizing appropriate EPA methodologies Subsequent to sample collection, any void created by the Soil Probe Unit will be grouted to the surface with a neat cement grout Any soil cuttings generated during sampling activities will remain on site underlain and covered in plastic sheeting pending analytical results of soil samples w\96731\ssiwkp doe 3 • SMTH