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Brownfields Site Assessment June 2014 South Gifford Road Landfill. Vero Beach, Florida dissolved plume. The boundary of the excavation footprint for the aggressive source removal, recovery wells and infiltration gallery injection wells associated with the IP&T system, and VOC groundwater monitoring network are shown on Figure 2. A refined source assessment was conducted in May 2003. Soil cores were screened using a photoionization detector (PID) to evaluate total VOC concentrations in soil. PID responses were generally elevated within the organic interval identified at approximately 12 to 13 ft BLS, which ranged in thickness from about 4.5 to 6 ft thick (zone of maximum PID response typically encountered within a 1.5 to 2.0 ft thick interval). High VOC field screening results in soil were observed in the organic -rich layer. Based on the results of the refined source assessment, source removal activities were conducted from May through October 2004, and resulted in the removal of approximately 800 to 1,200 pounds (lbs) of trichloroethene (TCE) from the source area via the excavation, and an additional 80 lbs of TCE, 73 lbs of cis-1,2-dichloroethene (cis-1,2-DCE), and 2 lbs of vinyl chloride via the dewatering system. Enhanced bioremediation injection activities were completed in 2008 and 2012 in the excavation footprint, along the eastern landfill property boundary, and east of the landfill property in conjunction with long-term groundwater monitoring to monitor the progress of ongoing biodegradation and natural attenuation at the Site. The current remedial strategy for the Site is a passive solution, which relies on the in situ biological degradation of VOCs. While the time to ultimately achieve cleanup standards using this approach is extended, the approach avoids the considerable costs associated with a more aggressive treatment system with mechanical components (such as plume -wide air sparging or pump and treat). Additionally, as part of separate work performed for IRC, in December 2008, test pits were excavated at the Site to assess the nature and extent of landfill material in the subsurface for purposes of potential redevelopment as a Senior Resource Center. Test pits were excavated at 17 locations (TP -01 through TP -17) in the northeast portion of the IRC -owned parcel at the former Humane Society building site (formerly located along 41St Street east of GR-MW30 and west of GR-MW09) and the Road and Bridge laydown yard. Test pit locations are shown on Figure 2. 2.4 Site -Specific Lithology The subsurface lithology at the Site has been characterized as part of assessment activities at the Site. The shallow sediments at the Site consist of 10 to 18 ft of fill where waste is present, along with organic rich native sands in unfilled areas. The underlying soil material consists of loose to medium dense sand with varying amounts of silt, to depths of approximately 30 to 40 ft BLS. Below this zone, fragmented shells intermixed with phosphatic sand, can be found to depths of approximately 65 to 75 ft BLS. The shell and sand layers are underlain by a zone consisting of FR0766H 4 7/8/2014