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�qw�u� Working to Restore Nature FIELD PROCEDURES Site Safft Plan Field work performed by RESNA on behalf of Unocal at the project site was conducted in accordance with RESNA's Site Safety Plan 38032-935, dated January 1993 This plan describes the basic safety requirements for the subsurface environmental investigation and the safety requirements for soil borings at the site The Site Safety Plan was applicable to personnel and subcontractors of RESNA. RESNA's personnel and subcontractors scheduled to perform work at the site were briefed on the contents of the Site Safety Plan before work began A copy of the Site Safety Plan was available for reference by appropriate parties during the work The onsite geologist of RESNA acted as the Site Safety Officer Soil Boring The soil boring was hand-augered to a depth of approximately 5 feet below grade The equipment was steam-cleaned before augering the borings to minimize the possibility of cross-contamination The soil borings were then drilled with a Mobile B-57 drill rig equipped with 10-inch-diameter, hollow-stem augers Upon reaching total depth in the boring, the boring was then grouted to surface with neat cement. • Soil Sampling in Borings Soil samples were collected at approximately 5-foot intervals from the ground surface to the full depth of the borings Soil samples were collected using a California-modified split- spoon sampler, equipped with clean brass sleeves Samples were collected by driving the sampler into the native soil at the base of the boring The sampler was driven through the hollow center of the auger into the soil The sampler was driven 18 inches with a standard 140-pound hammer repeatedly dropped 30 inches The number of blows needed to drive the sampler each successive 6 inches was counted and recorded to evaluate the relative consistency of the soil Sampling equipment was cleaned between each use with an industrial soap and clean tap water During sampling, the geologist used a field photoionization detector (PID) to characterize the relative levels of hydrocarbons. Field instruments such as the PID are useful for indicating relative levels of hydrocarbon vapors, but do not detect concentration of hydrocarbons with the same precision as laboratory analyses One of the samples in brass sleeves not selected for laboratory analysis at each sampling interval was tested in the field using a PID This testing was performed by placing the sample in a resealable plastic bag, manually breaking up the sample in the sealed bag, and allowing the contents to warm momentarily The intake probe of the PID is then inserted into the bag and the reading recorded on the Log of Boring 1214dcam/38032-14