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. 7 V Boring B-6 on Parcel 6 was advanced in the area of a possible radar anomaly. TRPH was not detected and the selected trace elements were in concentrations considered typical for the soil and geology of this region (Shacklette and Boerngen, 1984). Conclusions and Recommendations A reconnaissance of Parcels 5 and 6 was performed using the work plan developed by the San Joaquin Regional Rail Commission. Exploratory borings were advanced in areas of potential contaminant sources and ground penetrating radar anomalies on the parcels. Soil sampling and chemical analysis shows that petroleum contaminants are present at Boring B-2 where an underground storage tank was reportedly located. The area of the former battery storage are has been backfilled with artificial fill and chemical analysis for trace elements and VOC indicates that contaminants are not present. Boring B-6 drilled on Parcel 6 revealed that contaminants were not detected. Hand excavation at radar anomalies HA-4 and HA-5 indicate areas of backfill with concrete rubble, sand and asphalt. It is surmised that railroad tracks or other structures were removed and the holes backfilled with material at hand at that time. TPHG and Toluene,Ethylbenzene and Xylenes contaminants are present at B-2 at he former underground storage tank. It is our understanding that the tank source has been removed. The concentrations observed indicate biodegradation has occurred and the leak/spill is relatively old, and very low concentrations of these contaminants were detected at a depth of 21.5-feet. This occurrence should be reported the regulatory agency for review. Additional work, if needed, can be done to address the regulatory requirements for the site. Following any additional work, a request for site closure would be made to PHS-EHD. Limitations This report has been prepared specifically for the proposed Stockton Multimodal Station Site in Stockton, CA and was done according to the State and local suggested guidance documents for these investigations. The interpretations, conclusions and recommendations are based upon the data and analyses performed for this study and should be reviewed in the context of the whole report. Subsurface conditions could change in areas away from the boreholes where these samples were collected. PIease note that contamination should be reported to the proper agencies in a timely manner. Wright Environmental Services, Inc. is not responsible for errors in laboratory analysis or reporting, nor for information withheld during the course of the study and no warranty or guarantee is expressed or implied therein. If you have any questions, please call. Sincerely, E R Wright Environmental Services, Inc. N° 1262 � CERTIFIED John Lynch Christopher M. Palmer ENGNEE INN President C. E. G. 1262 � GEOLOGIST Attachments: Figure 1. Borehole Location Map �qTE OF CAu ��,P Exploratory Boring Logs Chemical Analytical Reports and Chain-of-Custody Forms "R" Value Physical Test Results Page 5