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Forward Landfill Hydraulic Testing Technical Memo July 03, 2019 • After completion of the pumping tests, the water level data were downloaded from the transducer data loggers for analysis. Specific capacity trends were plotted to enable assessment of drawdown against the step test pumping rates and for estimation of optimal pumping rates. The GWTS was restarted on May 3, 2019. Pre-Test Well Inspections Prior to conducting hydraulic testing each of the extraction wells were physically inspected, including well head condition,flow gauges and totalizers. The flow gauges for extraction wells EW-1 and EW-2 were found to intermittently stop under low flow conditions, but this this did not affect flow estimations at higher rates and their accuracy was tested by comparison to the flow gauge entering the groundwater treatment system, the readings were comparable at higher rates so the gauges were used for testing. EW-1 Step Test Assessment Step testing was conducted on EW-1 on May 2, 2019. The hydrograph for the step test is provided in Attachment A and field data sheets are presented in Attachment B. Manual water level readings for the pumping well and any adjacent wells are summarized in Table 2 and the step testing results are presented in Table 3 and in Figure 2. Step testing was conducted in five steps at rates of 10.0, 18.0, 35.2, 52.0 and 75.0 gallons per minute (gpm). The step tests indicated a specific capacity between 5.3 and 9.9 gallons per foot of drawdown • (gal/ft drawdown), with the final step at 9.9 gal/ft drawdown (Table 3). The drawdown at a rate of 75 gpm was 7.6 ft(62.9 ft below top of casing [btoc]), which corresponded to a pumping level of approximately 26.3 ft above the top of screen, with a drawdown of approximately 12%of the water column.A pumping rate of approximately 100 gpm could be achieved with drawdown of 9.7 ft, 16%of the water column, the water level approximately 24.2 ft above the top of screen. During the step test,the drawdown-discharge trend between steps was linear and the well and/or aquifer capacity were not stressed at the test pumping rates, with the well and aquifer able to produce more water than the current pump capacity if required. The drawdown trend during step testing of extraction well EW-1 indicates that the potential production rate for this well is in the order of 90 gpm potentially up to 140 gpm. The conveyance line capacity was increased in June 2019 and the production capacity increased to 95 gpm. If required, production rates above 95 gpm would require additional upgrades to the conveyance line and/or pump capacity and/or well rehabilitation. Review of the drillers log indicates that the entire 28 ft of screen interval are located adjacent to permeable sand rich materials. Manual water level readings collected from groundwater monitoring wells AMW-4(located approximately 390 ft from EW-1, screened shallow), AMW-6(located 16.7 ft from EW-1, screened in the deep zone) and AWM-8(located 31.5 ft from EW-1 and screened in the intermediate zone)all displayed a drawdown response to pumping EW-1, therefore indicating a degree of hydraulic connection to the pumping well. The pumping duration was relatively short and groundwater drawdown equilibrium was not reached, so a hydraulic connection is all that can be concluded. • arcadis corn FL Specific Capacity Test Memo 07032019.docx Page: 2/7