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Forward Landfill Hydraulic Testing Technical Memo July 03, 2019 of the water column.A pumping rate of approximately 50 gpm can be achieved with drawdown of 28.5 ft, 43%of the water column, the water level approximately 9.7 ft above the top of screen. During the step test,the drawdown-discharge trend between steps indicated a loss of capacity after 54 gpm, likely corresponding to when drawdown reached the top of the screen interval. The drawdown trend during step testing of extraction well EW-4 indicates that the optimal production rate for this well is in the order of 45-55 gpm. The conveyance line capacity was increased in June 2019 and the production rate was balanced at 45 gpm.This rate is likely optimal for the current well capacity, based on the discharge drawdown trends observed for the well step test. If higher production rates were required,this would require well re-development to be conducted. Review of the drillers log indicates that the entire 30 ft of screen interval are located adjacent permeable sand rich materials. Both extraction wells EW-1 and EW-2 produce significantly more water than EW-4,and EW-2 was indicated to have less permeable materials located adjacent to the screen interval. This indicates that EW-4 will likely produce more water with re-development. Manual water level readings collected from groundwater monitoring well AMW-4(located approximately 500 ft from EWA screened deep). Monitoring well AMW-4 displayed a slight drawdown response to pumping EW-4,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. Groundwater Capture Assessment Groundwater capture assessment was performed using the United stated Environmental Protection Agency(USEPA 2008)capture zone evaluation guidance. This method utilizes estimations of the hydraulic gradient,transmissivity and pumping rate to calculate the capture zone, which is illustrated in the footnotes to Table 8. As part of the calculations transmissivity values were derived from previous hydraulic testing results (Arcadis,20192), using an aquifer thickness determined from permeable materials identified on the respective well drilling log. A hydraulic gradient of 0.002 was used, based on previous interpretations groundwater monitoring data (2016 to present),where the hydraulic gradient has varied from 0.001 up to 0.003 depending on the season,with drier months typically having a lower gradient. A groundwater hydraulic gradient of 0.002 represents the average. The regional groundwater flow pattern is orientated towards the northeast. Groundwater flow in the western corner of the POC has been indicated as locally oriented in a north-northeasterly direction, based on review of previous groundwater flow maps and interpretation of the static readings collected as part of this assessment. The localized groundwater flow trends are likely influenced by several factors including the recharge basins,the ephemeral stream located 200 ft to the north of the Forward landfill and seasonal agricultural pumping. 2 Arcadis 2019,Well Installation and Hydraulic Testing Summary Report for Forward Landfill, San Joaquin County, California, dated April 15. arcadis com FL Specific Capacity Test Memo 07032019.dccx Page: 4/7