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Mr. Brendan Kenny July 03, 2019 The extraction wellhead will be completed to enable installation of a well header and permanent pump connection to the existing extraction conveyance system, set in Portland Type 1/II cement,with the cement installed from the top of the grout to the ground surface including a 4-foot wide concrete apron. The production casing will be temporarily capped with a J-plug. Upon completion of the extraction well it will be surveyed by a California licensed surveyor, using North American Vertical Datum of 1988(NAVD 88). Well Development and Rehabilitation The newly installed extraction well (EW-5)will be developed no sooner than 48 hours after installation to allow adequate time for the well seals to cure. The well will be developed by surging, bailing and over- pumping pumping to remove sediment introduced during drilling and/or well construction. Existing extraction well EW-4 will be re-developed as above and will also likely include scrubbing and chemical treatment with an acidic solution to remove scaling and/or biofouling. During well development, the volume of solutions added,water removed, and field parameters will be measured, including pH, electrical conductivity, turbidity, oxidation-reduction potential, dissolved oxygen, and temperature. Development will continue until the turbidity is reduced below 5 nephelometric turbidity units and parameters stabilized (less than 10%variation in readings). During development the extraction rate and water levels will be assessed to provide estimates of change in the well specific capacity. Hydraulic Testing Step-drawdown tests will be performed on groundwater extraction wells EW-4 and EW-5 after rehabilitation/development has been completed.The data obtained from these tests will be used to establish the specific capacity of each well, determine the optimal pumping rate and to enable permanent pump specification. Prior to performing the step-drawdown test,the well development data and associated drawdown trends will be reviewed to preliminarily assess achievable pumping rates.The hydraulic test pump will be specified to have a maximum pumping rate that is close to, or exceeds, the anticipated well capacity, likely in the range of 100 gallons per minute(gpm). The step-drawdown tests will be performed by pumping the extraction well at a set of sequentially increased pumping rates. The methods will be in accordance with those used for prior hydraulic testing conducted (Arcadis, 20182)and are summarized as follows. The water level in the pumping well will be monitored immediately prior to and during the testing using a pressure transducer, as well as manual water-level measurements.Water-level monitoring will continue through the well recovery period. The well header and pipework will be configured for the flow gauge and totalizer to be placed in a straight section of pipework to avoid turbulent flow conditions and with flow restricted by an in-line gate valve or equivalent. During testing, manual water-level measurements will be collected using an electronic water-level indicator with gradations to the nearest 0.01 foot before testing to determine static water levels, as well as ® 2 Arcadis 2018,Workplan for Well Installation and Hydraulic Testing at the Forward Landfill, San Joaquin County, California,dated November 16 arcadis com Page: Forward LF GWTS Upgrade WP 07032019.docx 5/7