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present beneath the site. Laboratory results for water samples collected from the perimeter of the property indicate that migration off-site of significantly (above State Action Levels) contaminated groundwater has not occurred. The source of the soil and groundwater contamination at the project site is undoubtedly crude petroleum pipelines that formerly transacted the property. Soil and groundwater in several areas in and around the city of Tracy have been contaminated by former petroleum transfer and storage facilities (American Management, 1985). The soil contamination recorded in the borings lies within the zone of seasonal groundwater fluctuation. The source of contamination (pipeline) at this site was removed at least 15 years ago and residual soil contamination left after pipeline removal has had a negligible impact on the shallow groundwater. This is indicative of the very limited mobility of crude oil within the soil and groundwater environment. Additionally, the toxicity of the hydrocarbon compounds remaining is extremely low. It is largely apparent that natural biodegradation processes have largely mitigated the problem at this site. Sampling has shown an insignificant impact to the shallow groundwater which, in any event, is not utilized for beneficial use. We recommend verification sampling of the wells followed by site closure if the initial results are confirmed. 5.0 REFERENCE American Environmental Management Corporation, Environmental Contamination Evaluation Tracy Parcel, APN 235-15-22, 1985, 7 pp. American Environmental Management Corporation, Environmental Evaluation Tracy Parcel, APN 235-15-22, 1988, 17 pp. Hotchkiss, W.R. and Balding, G.O. 1971, Geology, Hydrology, and Water Quality of the Tracy -Dos Palos Area, San Joaquin Valley, California, USGS Open -File Report, 104 pp.