ARCHIVED REPORTS XR0009324 - Laserfiche WebLink

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3.2 Drilling, Logging and Soil Sample Collection V & W Drilling was contracted to drill and sample three (3) soil borings, and to convert one (1) of these soil bonngs into a groundwater monitoring well Bore holes for the groundwater monitoring wells were drilled using a truck-mounted, hollow stem auger drill ng The bore hole diameter was 8 inches A Califorma Registered Geologist from Ramage Environmental logged each bore hole during drilling and constantly checked the drill cuttings for indications of both the first recogruzable occurrence of groundwater and contaminants A portable photoionization detector (PID) (corroborated by odor) was used to determine the occurrence of contaminants For all borings, a split-spoon sampler was driven at five (5) foot intervals into the bottom of each soil boring by a 140-pound drop hammer as the boring was advanced, through the hollow stem of the 8-inch diameter continuous-flight auger The sampler was extracted from the bore hole and the brass tubes, containing the soil samples, were removed Upon removal from the sampler, the selected brass tubes were immediately trimmed and capped with Teflon sheets and plastic caps The samples were then labeled and placed in a cooler of ice for delivery, under chain-of- custody protocols, to the analytical laboratory The analytical laboratory selected for sample analysis was Precision Enviro-Tech Analytical Laboratory in Stockton, California A portion of each soil sample collected was analyzed in the field using a PID The purpose of this field analysis was to qualitatively determine the presence or absence of volatile petroleum hydrocarbons The portion of soil was sealed in a Ziploc plastic bag and left in the sun to allow r for volatilization of VOC's, if present The PID was then used to measure the concentrations of r hydrocarbons within the headspace inside the plastic bag The data were recorded on the boring logs at the depth corresponding to the sampling point (see discussion of PID data in Section 4 2 r and Soil Boring Logs in Appendix A) Each boring was advanced slowly to allow for identification of changes in soil types The soil boring was logged and soils described in accordance with the Unified Soil Classification System (USCS) Potable tap water was available at the site for hydrating the bentonite chips, mixing grout and washing sampling tools Drilling tools were pre-cleaned using high-pressure steam by V & W Drilling Auger cuttings were placed in labeled 55-gallon drums and were stored at the site for Envwroneermg,Inc Project No 00-01108 4