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IM 4Y u s . 70 d , _ OWENfw _ 4 FW , .w drilling was performed under the direction of a field geologist who maintained a continuous log of the materials encountered using the Unified Soil Classification System (Appendix I) . 2.2 Monitoring Wells The two soil borings were completed as two inch diameter ' monitoring wells. The wells were sited in the assumed downgradient direction based on previous monitoring. Specific details of the construction/ completion are included on the Individual logs (Appendix Y ) . Subsequent to completion, the wellheads of all wells were surveyed and elevations tied to a common datum. Water level j meazurements, summarized in Table 1, were taken after development using an interface probe In accordance with ._ WaterWork's Groundwater Monitoring Protocol (Appendix II) . No free product was noted in any of the wells. Water ^ samples were collected from wells MW3, MW4, MW5 and MW6 following Water Work's Groundwater Sampling Protocol (Appendix II) . The ' samples were analyzed for benzene, _. toluene, ethylbenzene, xylene, (BTEX) and total petroleum hydrocarbons (TPH) by EPA mdthods 8015 and 8020. 2.3 Tank Pit Sampling Six .5011 samples were collected from tank pit A, two from the floc.-. and one from Each wall. The samples were �- collected in accordance with WaterWork's Soil Sampling Protocol (Appendix II) . The pit floor samples were composited as well as the north and west walls and south and east walls. The three samples were analyzed for BTEX (EPA 8020) and TPH as gasoline (DOHS Method) . 3.0 FIELD INSPECTION The soils encountered during drilling consisted of clays, - sandy and gravely clays, and silty sands to 25 feet, the maximum depth explored. Field inspection did not note the presence of hydrocarbon odors in soils from the two borings. Groundwater was encountered at approximately 16 feet below grade and rose to approximately 8 feat after well completion. This rise in water level together with the lithology of the borings suggests that the first groundwater is confined or semi--confined at this site. The groundwater gradient, calculated from the April 13, 1985 monitoring is a .3 percent in a westerly direction (Figure 3) . Laboratory.-,analysis--of..sol l..-samples--collected -from tank ..-.pit A did not record concentrations of gasoline hydrocarbons above method detection limits. The laboratory reports and chain-of-custody form are presented in Appendix III. Laboratory analysis of groundwater samples reccrded k all 21 111