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Mr. Geoffrey Rader <br /> Page 3 of 7 <br /> Free Product Measurement and Recovery <br /> On December 19, 2018, and March 20, 2019, a Ground Zero technician monitored wells MW6R, <br /> MW8, MW9R and VEW1-D for the presence of free product using an interface probe. No free <br /> product was present in wells MW6R, MW8,MW9R and VEW 1-D during either monitoring event. <br /> In total, approximately 131 gallons of free product/water mixture have been removed from well <br /> MW6R since October 2007; approximately 946 gallons of free product/water mixture have been <br /> removed from well MW8 since April 1994; a total of approximately 528 gallons of product/water <br /> mixture have been removed from MW9/MW9R since October 2003; and approximately 125 <br /> gallons of free product/water mixture have been removed from VEW 1-D since June 2010. Product <br /> thickness and recovery data for well MW6R are summarized in Table 4; data for well MW8 are <br /> presented in Table 5; data for well/s MW9/MW9R are presented in Table 6; and data for well <br /> VEW 1-D are presented in Table 7. Field notes are included in Attachment A. <br /> Groundwater Sampling <br /> Groundwater sampling at the site was conducted in accordance with the sampling schedule set <br /> forth in the MRP. All purged groundwater was contained in appropriately labeled,DOT approved, <br /> 55-gallon drums, which are stored onsite. Well monitoring and purge logs are included in <br /> Attachment A. <br /> On March 20,2019,groundwater samples were collected from wells MW3,MW6R,MW7,MW8, <br /> MW9R, MW 13 and VEW 1-D for analysis. Monitoring wells MW2, MW4, MW5, MW 10, <br /> MW 11, MW 12, MW 14 and MW 1 D were not sampled because those wells are sampled annually <br /> during the second half of the year. Prior to sampling, each well was purged of at least three well <br /> casing volumes of groundwater. During the purging process temperature, electrical conductivity <br /> and pH parameters were measured. Subsequent to parameter stabilization and appropriate <br /> groundwater recovery,water samples were collected from the wells,placed into an ice chest cooled <br /> to approximately 4'C, and delivered under chain-of-custody protocol to BC Laboratories, Inc. (BC <br /> [ELAP No. 118 6])for analysis. Pursuant to the MRP,the samples were analyzed for TPHg,BTEX <br /> compounds and oxygenates by the appropriate EPA Methods. Additionally, the samples from <br /> wells MW6R, MW8, MW9R and VEW1-D were analyzed for TPHd by the appropriate EPA <br /> Method. <br /> Soil Vapor Extraction System Operation <br /> The soil vapor extraction(SVE) system was installed and started up during the third quarter of 2012. <br /> The SVE system was shut down in September 2018, after rebound testing confirmed low mass <br /> removal rates. The system was not operated, monitored or sampled during the fourth quarter of <br /> 2018 or the first quarter of 2019. Since the initiation of soil vapor extraction in August 2012 through <br /> September 12,2018,the SVE system operated for a total of 28,136 hours and removed approximately <br /> 19,150 pounds of hydrocarbons from the subsurface. <br /> The location of the SVE system, the equipment compound and the extraction wells are shown on <br /> Figure 2. Vapor extraction system monitoring and hydrocarbon mass removal data are <br />