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Mr. Himanshu H. Mehta, P.E. 25 September 2020 Page 6 historical groundwater and surface water quality data. It should be noted that upon the generation of this database, it will be easier to analyze trends going forward at the Site as part of the groundwater monitoring program. Phase 2 — C&D Debris Disposal Facility Supplemental Groundwater Assessment Quarterly assessment is currently being performed on the eastern side of the C&D debris disposal facility to monitor conditions of groundwater and surface water to meet objectives outlined by FDEP electronic mail (e-mail) correspondence dated 10 June 2019, 22 August 2019, and 3 October 2019. A supplemental groundwater assessment is required to evaluate the groundwater conditions between the C&D debris disposal facility/RDF and the Lateral C Canal to the east. Specifically, the dimensions of the plume consisting of elevated conductivity and nutrients need to be characterized in order to assess remedial alternatives including groundwater extraction via TreeWell phytoremediation technology. In order to accomplish this objective, a supplemental groundwater assessment is recommended consisting of groundwater screening followed by the installation of temporary piezometers at targeted intervals. Groundwater screening will be completed by advancing a 5 -foot stainless steel slotted screen and using direct push technology (DPT) methods. The focus of the groundwater screening will span from the water table to an approximate depth of 25 feet (ft) below ground surface (bgs). Groundwater will be purged from each 5 -ft interval and screened with a water quality probe capable of monitoring temperature, pH, conductivity, oxidation reduction potential (ORP) and ammonium. Turbidity will also be monitored using a turbidimeter. Each groundwater screening interval will be purged at least 3equipment volumes until stability of field parameters is achieved per FDEP Standard Operating Procedures (SOPs) or a maximum purging period of 30 minutes. It is estimated a total of six (6) locations will be screened with the approximate locations summarized below. Locations may be adjusted based upon the results of the initial screening locations. The intent is to delineate the north/south extent of the elevated conductivity and nutrients in groundwater. Each location will be abandoned with tremie applied cement grout slurry. NCP2020 3158/JL200925 2020 Compliance Monitoring Proposal