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S Groundwater Gradient Groundwater elevations were plotted to a known datum to prepare a groundwater contour map The groundwater flow direction was toward the north-northeast at sampling time, and a flow gradient of 0 031 was calculated Water levels have risen slightly, and this is attributed to normal aquifer recharge Historic groundwater flow trends typically vary from north- northeasterly to north-northwesterly Chemical Analysis and Results The samples were transported to Chromalab, Inc in Pleasanton, CA The groundwater samples were analyzed using EPA Methods 5030/ 8015 and 602 for Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and fuel oxygenates including Methyl-tert-butyl-ether (MTBE) by EPA Method 8260 The analytical reports are attached, and the results are listed below in Table 2 (see Table 3 for historic data) Table 2. Groundwater Chemical Data Well No Date TPHG' Benzene Toluene Ethylbenz Xylene Fuel Ox ------------------------------- u g/l ----------- ---------------- MW-1 12/29/98 9,100 910 150 990 840 ND MW-2 12/29/98 ND NO ND ND NO NO MW-3 12/29/98 ND ND ND ND ND NO MW-4 12/29/98 ND ND ND ND NO NO Blank 12/29/98 ND NO ND ND ND NO ND - None detected NA - Not Analyzed ug/I - micrograms per liter Fuel Ox - Fuel oxygenates including MTBE by Method 8260 1,2-Dichloroethane NO for all wells for 12/29/98 sampling Discussion Groundwater flow direction appears consistent with historically observed trends The concentrations in Well MW-1 are similar to the previous quarter and are attributed to residual contaminants desorbEng into the groundwater from the soil strata in the immediate vicinity of the former tank pit MTBE was not detected in any well Well MW-4 showed contaminants not detected Conclusions and Recommendations Wright recommends that the quarterly monitoring for this site continue at quarterly intervals Page 3