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Work Plan to Install Compliance Groundwater Monitoring Wells,Musco ' Family Olive Company,Tracy,California bottom up (Figure 4). A threaded schedule 40 Polyvinyl Chloride(PVC)groundwater monitoring well will then be constructed.The monitoring wells will be constructed to provide a low turbidity groundwater ' sample and to accurately reflect the potentiometric surface at the monitoring well location. The screened interval will extend across the water bearing zone or a maximum of 20 feet total.As the ' augers are being removed,the annular space between the well screen and the formation will be filled with No. 2/16 sand to a depth of approximately 2 feet above the screened interval.The well screen will t be positioned within the boring to screen across the depth of the first encounter of groundwater. Based on previous groundwater monitoring well installations at the Musco facility,the first water bearing zone may be under pressure and therefore the water level may rise in the well casing to an elevation ' shallower than the water bearing formation.Therefore,the screen interval will be constructed to span the first water bearing formation,to a maximum screen length of 20 feet.A California Professional Geologist will approve the final placement of the screened interval. ' Approximately 2 feet of bentonite chips will be placed above the sand pack and hydrated to form a coherent seal.The bentonite seal will be placed in two lifts of approximately 1 foot each. Each lift will be ' hydrated with potable water in such a way as to prevent the displacement of the bentonite material. The bentonite seal will be allowed to hydrate in accordance with the manufacturer's recommendations. The remaining annular space above the bentonite will be filled with cement grout.A locking well cap will ' be placed on top of the well casing, and the well will be completed using an above grade well vault.The well construction details will be recorded onto a soil boring/monitoring well construction log ' (Attachment 1).The elevation, northing, and easting of each newly installed monitoring well will be surveyed by a California-licensed surveyor following installation.These data will allow for the measurement of groundwater elevations and the assessment of groundwater flow direction. ' The newly installed monitoring wells will be developed to remove sediment from around the screen and to enhance hydraulic communication with the surrounding water bearing formation.The grout installed ' within the annular seal for the monitoring wells will be allowed to cure for a minimum of 72 hours before initiating well development activities.The wells will be developed using a combination of surging and pumping techniques. Observations of indicator parameters, including pH,temperature,specific ' conductance, quantity, and clarity,will be recorded onto water-quality data sheets after each well volume is purged. In the event that a well recovers slowly,the well will be purged dry and then allowed to recover to approximately 80 percent of its static water level before being purged dry again.The wells , will be developed until a minimum of 6 to 10 well casing volumes are removed, relatively sediment-free water is produced,or indicator parameters stabilize in accordance with the following criteria: ' Parameter PH Conductivity ORP Turbidity DO Stabilization ±0.1 units ±3% ±10 ±10% ±10% ' Criterion mV Notes: ' DO=dissolved oxygen my=millivolts ORP=oxidation reduction potential , Terraphase Engineering Inc. Page 4 of 6