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v Work Plan-Soil and Groundwater Investigation New Jerusalem school October 26,1998 Page-2- the proposed boring locations are on private property, utilities contacted by USA will not mark their lines past property boundaries and into the site. Therefore, it is the responsibility of New Jerusalem School to locate and identify underground utilities in and near the work area. W 3.2 DRILLING PROCEDURES The proposed drilling methods include hollow stein auger for the installation of three monitor wells and the three soil borings. Hydropuncli technology will be used for the purpose of collecting shallow groundwater samples. See Figure 2, Appendix A for proposed drilling locations. All drilling activities will be performed under the supervision of a Condor geologist_ V 3.3 SOIL BORINGS AND GROUNDWATER SAMPLING The three soil borings will be advanced to an estimated depth of approximately I2 feet bgs to collect soil y samples in the vadose zone and groundwater samples from the groundwater table. .Prior to commencement of fieldwork, a tailgate safety meeting will be held and the site-specific Health and Safety Plan will be discussed with and presented to all crewinembers for their signatures. The soil borings will be drilled by Spectrum Exploration of Stockton, California(C57 Iicense 9512268). A Condor geologist will be on site to supervise the drilling, soil sampling, and well installation. The proposed soil boring locations are shown on Figure 2,Appendix A_ The soil borings will be drilled using 6-inch O.D., contInUOUS-flight,Hollow-stem auger. The auger will be steam cleaned before each borehole is drilled. The soil sampling equipment(i_e., split-spoon)will be cleaned prior to collecting each sample. �. The cleaning procedures will consist of washing the sampling spoof in a solution of laboratory-grade, non-phosphate detergent and hydrocarbon-free water,and double rinsing with hydrocarbon-free water. A maximum of three soil samples will be collected from each soil boring. One soil sample will be collected from a depth of approximately 5-feet bgs, one from i 0-feet bgs, and one soil sample will be collected from the capillary fringe if the capillary fringe is located below 12 bgs. If significant lithological changes are encountered during the installation of the monitor wells, a soil sample will be collected from each significant lithologic unit for laboratory analysis. Soil samples will be collected in each borehole using a California-modified, split-spoon sampler fitted with three clean, brass liners. During the sampling, the split-spoon sampler will be driven ahead of the auger. The uppermost liner will be discarded. The middle sample liner will be used for geological logging and for field screening using an organic vapor analyzer (OVA) and the bottommost liner will be prepared, as described below, for possible shipment to the laboratory. The soil samples will be logged according to the Unified Soil r✓ Classification System. Drilling logs will be prepared and will contain field observations including soil type, estimated moisture content, presence of staining or odor, and field OVA measurements. All soil samples collected for laboratory analysis will be retained, undisturbed, in the brass liners. The liners will be sealed at the ends with Teflon tape, capped, wrapped with duct tape, and labeled. The samples will be stored in a cooler chilled with Blue Ice and delivered within 24 hours of collection, under chain-of-custody procedures, to GeoAnalytical Laboratories in Modesto, California. Two soil samples from the vadose zone of each borehole will be selected for chemical analysis. One of the soil samples will be from the capillary fringe. LJ CONDOR