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Mr. Himanshu H. Mehta, P.E. 4 December 2020 Page 3 correspondence dated 14 October 2019 from FDEP to SWDD, the FDEP approved SWDD's request to replace the evaluation monitoring of the eight groundwater wells and surface water sample sites with quarterly assessment monitoring and with the addition of other parameters (arsenic, benzene, naphthalene, and other semi -volatile organic compounds [VOCs]) to the suite of parameters to be analyzed for at these wells. The FDEP also requested sampling of additional surface water sites in the Lateral C Canal for the purpose of establishing background water - quality conditions. Therefore, in 2020 Geosyntec working on behalf of SWDD sampled all seven surface water sites except for April 2020 where the FDEP agreed to a reduction to three locations. The reduction to three surface water sampling locations was a one sampling events approval and the total number of surface water sampling locations is assumed to be seven for the 2021 sampling events. However, Geosyntec will work with FDEP to reach an agreement on the optimal surface water sampling locations during the 2021 monitoring program in order to provide overall cost savings to the County. Therefore, in addition to the semi-annual sampling of the C&D debris disposal facility monitoring wells in January and July 2021, these nine wells and seven surface water sample sites will also be sampled in April and October 2021 as part of the 2021 compliance monitoring and reporting program. Geosyntec recently (in December 2020) conducted supplemental groundwater assessment in the vicinity of C&D debris disposal facility. This program might be amended based on the results of the supplemental assessment. Ouarterly Assessment Monitoring for the Class I Landfill A comment letter from FDEP dated 6 May 2020 provided comments regarding the results of the January 2020 Semi -Annual Water Quality Monitoring Report for the Class I landfill. FDEP provided notification to SWDD to initiate evaluation monitoring at all monitoring wells with detected exceedances above applicable groundwater cleanup target levels (GCTLs) for pH, ammonia, chloride, sodium, total dissolved solids (TDS) and arsenic. Geosyntec provided a response to comments (RTC) letter to the FDEP comment letter on 28 May 2020 which focused on the long-term trends with the dataset available from the FDEP Water Assurance Compliance System (WACS) database and requested a reduction of evaluation monitoring locations from 25 locations (as originally requested by the FDEP in the 8 May 2020 letter) to four (4) locations (specifically downgradient of MW -3S, MW -14S, MW -44S and MW -44I). FDEP approved this request in a letter dated 14 August 2020 and the 90 -day evaluation monitoring period was initiated on 17 September 2020 through a second RTC letter provided to FDEP. Geosyntec installed the three (3) groundwater evaluation monitoring wells in November 2020 (evaluation monitoring well not installed downgradient of MW -14S since MW -14S was already located at the edge of the Class I landfill zone of discharge), sampled the four (4) quarterly wells and NCP2020 3249/JL20060 2021 Compliance Monitoring Proposal