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moisture and consistency(in relative terms), and estimated degree of hydrocarbon content(PID measurements). Logs of the borings are presented in Appendix A. Selected soil samples from each borehole were submitted to a State of California-certified analytical laboratory(Chromalab, San Ramon) for chemical analyses. The soil samples were analyzed for total petroleum hydrocarbons as gasoline(TPH-G)by EPA Method 5030/8015,total petroleum hydrocarbons as diesel, kerosene and motor oil (TPH-D, TPH-K, and TPH-MO)by EPA Method 3550/8015,total oil and grease by Standard Method 5520 E&F, and benzene,toluene, ethylbenzene and xylenes (BTEX)by EPA Method 8020. TEMPORARY MONITORING WELLS AND GROUNDWATER GRAB SAMPLING Each borehole was completed as a temporary well (except B-1 which was completed as groundwater monitoring well MW-1) in order to facilitate the collection of groundwater samples for laboratory analyses, and to enable depth to water measurements to determine groundwater flow direction. The temporary wells were constructed by inserting pre-cleaned, 2-inch diameter, Schedule 40 PVC well screen and casing into the borehole prior to pulling the augers. A filter sock was placed over the well screen to control turbidity in the groundwater samples. After the augers were removed from the borehole,the top-of-casing elevations were surveyed to an existing benchmark (Geodetic Survey Hub No. W474 located at the west end of the Middle River bridge) in order to establish an elevation control point for depth to water measurements. Depth to water measurements were made in each temporary well after the water levels stabilized using a steel tape and chalk(accurate to 0.01 ft), and the water level measurements were subsequently converted to elevations. After water level measurements were completed in each of the temporary wells, approximately 2 to 3 well volumes of water were purged from the wells and groundwater samples were collected. A new bailer and bailer line was used for each temporary well. The groundwater samples were transferred from the bailer into two appropriately prepared 40-m1 volatile organic analysis (VOA)vials with caps having Teflon septums and one 1-1 amber bottle equipped with a Teflon-lined cap. Care was taken to avoid turbulence when transferring the water from the bailer to the containers. The containers were filled so that no air bubbles were present and were then placed in a cooler containing ice and chilled to less than 4°C. Each sample was labeled with the borehole identification information,the date of sample collection,the requested chemical analyses, and the initials of the sampling personnel. The water samples from each temporary well were submitted to a State of California-certified analytical laboratory (Chromalab, San Ramon) on November 25, 1992. The samples were analyzed for total petroleum hydrocarbons as gasoline(TPH-G) by EPA Method 5030/8015,total extractable petroleum cca/08/18/93/9449arpt.doc/mkn4 5-3