ARCHIVED REPORTS_XR0008238 - Laserfiche WebLink

Home Browse Search

3.0 CONCLUSIONS, RECOMMENDATIONS AND PROJECT STATUS Between May 9, and September 12, 2003, the groundwater surface dropped an average of 1 51 feet, the groundwater gradient increased from 0 0082 to 0 0113 foottfoot, and the groundwater flow direction shifted approximately 10 degrees toward the north The depth to groundwater beneath the site is at its lowest level, since the monitoring wells were installed in July 2002 Otherwise, the groundwater surface characteristics are consistent with historical trends Between May 9, and September 12, 2003, gasoline compounds in groundwater continued to be limited to MW-1, and in close proximity to the former UST During the quarter, the concentrations of gasoline compounds at MW-1 increased, probably due to seasonal variation Concentrations of gasoline compounds in groundwater have generally declined, since the monitoring wells were installed in July 2002, probably due to source removal efforts and natural attenuation processes The extent of impacted groundwater appears to be defined to the north by MW-2, and to the northeast (downgradient) by MW-3 To date, the source of gasoline has been removed, the downgradient extent of the plume of impacted groundwater has been defined, and concentrations of gasoline compounds in groundwater appear to be degrading No sensitive receptors appear to be threatened by the gasoline compounds in soil and groundwater beneath the site Based on these conditions, Ramage Environmental recommends that EHD and RWQCB consider the case for regulatory closure In the meantime,the three monitoring wells should continue to be monitored and sampled on a quarterly basis The next monitoring event is scheduled for December 2003 7