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1 ' 4.0 CONCLUSIONS 4.1 Groundwater Flow Direction and Gradient ' JJW prepared a groundwater potentiometric surface map based on the static groundwater elevations measured on November 27, 2001. The shallow groundwater was calculated to flow ' toward the north (N 6 W) at a gradient of approximately 0.0052 ft/ft. Figure 3 illustrates the groundwater potentiometric contour surface and flow direction. ' 4.2 Groundwater Contamination Groundwater contamination was detected in monitoring well MW-2 with a very low level of benzene detected in MW-5. The groundwater contamination in MW-2 consisted of total ' petroleum hydrocarbons as gasoline, and associated aromatic volatile fuel components (BTEX). No contamination was detected in the other three wells. No MTBE was noted in any of the five wells. ' The groundwater contaminant plume in the vicinity of well MW-2 and adjacent MW-5 is inferred to extend down-gradient of well MW-2 approximately 30 feet. The plume is inferred to extend up-gradient and cross-gradient approximately 5 and 20 feet, respectively. Figure 4 illustrates the inferred limits of groundwater contamination for the November 2001 sampling event. ' 5.0 RECOMMENDATIONS ' The contaminate levels are now low enough to consider this site for closure. JJW is in the process of putting together a site closure report. ' 6.0 LIMITATIONS ' The lack of identification of contamination on a site does not preclude its existence. I Geosciences incorporates the current, standard of care when making judgments concerning the presence of contamination on a site. However, due to natural circumstances, it is not always possible to identify and/or accurately determine the presence of contamination. Additionally, changes in appropriate standards may occur, whether they result from legislation, the broadening of knowledge, or other reasons. Such changes may invalidate certain findings of this report. ' This report has been prepared for the exclusive use of the client and is applicable only for the pp Y subject site. I Geosciences is not responsible for interpretations by others of the data ' presented in this report. This report does not represent a legal opinion and no warranty is expressed or implied. ______=This report is issued with the understanding that it is the responsibility of the property owner to - - ensure that the information and recommendations contained herein are brought to the attention of the appropriate regulatory agency. This work was performed in accordance with the generally accepted standards of care existing in Northern California at the time of the . investigation. ' JJW GEOSCIENCES Inc. 3