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Mr. Geoffrey Rader Page 5 of 7 SUMMARY Water levels rose during the December 2018 monitoring event when compared to the previous monitoring event in September 2018. Groundwater flow in December 2018 was generally in a southerly direction, at a gradient ranging from approximately 0.005 to 0.02 ft/ft. Water levels rose between the December 2018 and March 2019 monitoring events. Groundwater flow in March 2019 ranged from a southerly to southeasterly direction, at a gradient ranging from approximately 0.003 to 0.02 ft/ft. No free product was measured in wells MW6R, MW8, MW9R and VEW1-D during the fourth quarter of 2018 and the first quarter of 2019. Approximately 131 gallons of product/water mixture has been removed from well MW6R since October 2007. Approximately 946 gallons of free product/water mixture has been removed from well MW8 since April 1994. Approximately 528 gallons of free product/water mixture have been removed from wells MW9/MW9R since October 2003. Approximately 125 gallons of product/water mixture have been removed from well VEW 1- D since June 2010. Due to the modified schedule put forth in the revised MRP, perimeter wells MW4, MW5 and MW 14, downgradient wells MW 10 and MW 11,upgradient wells MW2 and MW 12 and deep well MW1D were not sampled during the first quarter 2019 groundwater sampling event, but during previous sampling events they have remained free of any detectable levels of petroleum hydrocarbons or oxygenated fuel additives. Contaminant concentrations in the affected monitoring wells in March 2019 were generally within recent historical ranges with a few exceptions: the benzene and TPHg concentrations detected in well MW6R were the lowest since the well was first sampled in October 2005; the TPHg concentration detected in MW9R was the lowest ever detected for that well; and the benzene concentration detected in well MW 13 was the highest since the September 2011 sampling event. Graphs of TPHg, TPHd, benzene and MTBE concentrations over time in select site wells are included in Attachment C. The SVE system was installed and started-up during the third quarter of 2012. The system remained operation until June 5, 2017, when it was shut down for a period of rebound testing. On January 23,2018,the system was restarted for two hours for sample collection as part of the rebound test and then shut down. Based on the SVE system monitoring data collected on January 23,2018,it was estimated that the SVE system was removing approximately 0.2 pounds per day (lbs/day) of TPHg from the subsurface. On September 10,2018, at the request of the RWQCB,the SVE system was restarted for a second round of rebound testing and samples were collected at various intervals over a 48 hour period. After sample collection the system was shut down. The SVE system was removing TPHg at the rate of 0.4 lbs/day. To date, the SVE system has operated for 28,136 hours and has removed approximately 19,150 pounds of hydrocarbons from the subsurface. The system currently remains offline and it is not anticipated that the SVE system will be returned to operation. CONCLUSIONS AND RECOMMENDATIONS The operation of the SVE system has eliminated free product from the site. Lateral and vertical definition of the dissolved contamination plume is complete and concentrations overall have been