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Mr. Himanshu H. Mehta, P.E. 3 August 2021 Page 5 infrastructure and refine the understanding of the potential interconnection between the RDF and C&D debris disposal facility. Phase 3 — RDF and C&D Debris Disposal Facility Additional Assessment Phase 3, Task 1— Expanded Groundwater Assessment Five (5) additional groundwater screening locations (GSB-7 through GSB-11) are proposed along the stormwater management ditch north of the C&D debris disposal facility and south of the RDF to refine the understanding of the water quality distribution in this area. One (1) additional groundwater profiling location (GSB-12) is also proposed to the south of GSB-2 and GPZ-3 to laterally delineate the groundwater impacts to the south of the impacted area (Figure 1). The groundwater screening locations may be adjusted following the completion of Phase 2. Vertical groundwater profiling will be conducted on four -foot (4-11) intervals between the water table and a maximum depth of 36 feet below land surface (ft bls). Groundwater screening will be completed by advancing a 4 -ft 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 32 ft bls. Groundwater will be purged from each 4 -ft interval and screened with a water quality probe capable of monitoring temperature, pH, conductivity and oxidation reduction potential (ORP). Turbidity will also be monitored using a turbidimeter and ammonia will be monitored with a HACH field kit. Each groundwater screening interval will be purged at least 3 equipment volumes until stability of field parameters is achieved per FDEP Standard Operating Procedures (SOPs) or a maximum purging period of 15 minutes. Each location will be abandoned with tremie applied cement grout slurry once groundwater screening is completed. Phase 3, Task 2 — Stormwater Management Ditch Assessment The depth and nature of the sediments within the perimeter stormwater management ditch to the south of the RDF which conveys stormwater to the south and adjacent to the eastern edge of the C&D debris disposal facility will be assessed. The assessment will include the completion of eight (8) muck probes (MP -1 to MP -8) using either DPT methods or hand auger to estimate the depth of the sediment and the collection of analytical samples to evaluate the levels of nutrients. The sampling locations are distributed around the perimeter stormwater ditch to assess the potential distribution of nutrient inputs. Composite samples of the muck will be collected from each of the locations and analyzed for nitrogen species (nitrite, nitrate, ammonia, Total Kjeldahl NCP2020-3158/JL21057 GW Compliance Technical Support Services.doc