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J contamination was noted. A portion of the cored material was ' sealed and preserved using WJH standard field protocol described earlier. A change in penetration rate at about 28-29' indicated a softer ' material; drill cutting returns showed a small amount of coarse gravel_ A core wag taken from 30 ' -3V_6recovcary was 18" of tan to brown clay; crumbly to slightly plastic, with a mottled appearance. Some root casts were evident. No odor or other evidence of contamination was noted. A portion of the cored material was preserved per WJH field procedures_ ' The augers were advanced to 35' ; the drill cuttings just prior to taking the next core had a definite petroleum odor, with some apparent discoloration. A core was taken from 35' -36' 6 ' recovery consisted of 18" of sticky, dark tan to brown clay, slighty moist, with occassional sand grains scattered in the matrix. The core had a definite petroleum odor, and possable ' discoloration. A portion of the core was preserved as described earlier. The penetration rate decreased at 37' , indicating a change in lithology or change in density of the material Drill returns had a distinct petroleum odor. A core was taken from 40' -41 ' 6" ; recovery was 18" of silty clay, brown to gray mottled appearance, ' with a strong petroleum odor & apparent discoloration due to contamination_ ' The workplan had specified a maximum depth of 40' for the soil boring; however, after examining the last core, and noting that contamination was still present, it was agreed that drilling should continue. The augers were advanced another 5' , and a care ' was taken from 4 ' -4 ' 6" as directed by the geologist & Steve Sasson of the San Joaquin County EHD. Recovery consisted of 18" of sandy, sticky clay, brown to dark gray, with a mottled ' appearance. Some rust colored staining was apparent, (due to iron oxides; ) occassional streaks of fine to coarse sand were present. Although no visible contamination was apparent, the ' cored material had a definite petroleum odor_ Augers were advanced another 5' , and a core was taken from 50' - 52' 0" . Recovery consisted of 24" of sandy, silty clay, brown to ' gray, slightly plastic, dense. Core had a mottled appearance, due possibly to contamination. A definite petroleum odor was noted over the entire cored interval. One of the metal tubes was ' sealed and preserved for later analysis. Drilling stopped for about one hour at this point so that the drilling crew could get more drill rods to continue operations. There were sufficient auger flights on the rig; the support truck ' 6