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Work Plan Addendum to Install Compliance Groundwater Monitoring Wells Musco Family Olive Company Tracy California Given its proximity to monitoring well MW-35, it is expected that the lithology and depth to groundwater encountered at MW-35R will be similar to that recorded at MW-35.Therefore well construction details for monitoring well M-35R are expected to be similar to the construction details of MW-35(see details described above).The soil boring will be advanced to approximately 130 feet bgs.At 130 feet bgs,soil sampling will be initiated in five foot intervals to approximately 170 feet bgs. If groundwater is not encountered,the soil boring will be left overnight and the water level will be checked the following day. If a significant quantity of water is detected within the soil boring the following day,a monitoring well will be installed with a 20 foot screen interval(consistent with the procedures described in the Well Installation Work Plan). If groundwater is not detected in the soil boring after being left overnight,the well will continue to be drilled with sampling at 5 foot increments.The well will be drilled to the first encountered water or a maximum depth of 335 feet bgs(consistent with procedures described in the Well Installation Work Plan). If the maximum depth of 335 feet bgs is reached and dry conditions are still noted,a monitoring well will be constructed with a screen interval that ranges from 285 feet bgs to 335 feet bgs(consistent with the procedures described in the Well Installation work Plan). Piezometer Installation In January of 2014,Musco installed monitoring wells MW-33, MW-34 and MW-35 at the approximate locations illustrated on Figure 2.The monitoring wells were installed as compliance monitoring wells for the proposed surface impoundments. In accordance with Title 27 regulations,the monitoring wells were screened in the first encountered water bearing zone detected at each location.A summary of the screen intervals are provided below: • Monitoring Well MW-33:Screen from approximately 230.5 feet bgs to approximately 250.5 feet bgs. • Monitoring Well MW-34:Screen from approximately 104 feet bgs to approximately 114 feet bgs. • Monitoring Well MW-35: Screen from approximately 150 feet bgs to approximately 170 feet bgs. Based on the information recorded at each location,the monitoring wells are screened in separate water bearing zones.The well construction for MW-34 is consistent with the construction of wells located at the facility currently monitoring the existing surface impoundments.Therefore,the groundwater flow direction and gradient for the water bearing zone represented at MW-34 will be assessed in conjunction with monitoring at the previously installed monitoring wells. If the screen interval to be constructed at MW-35R is within the same water bearing zone detected at MW-35,then additional piezometers,as illustrated within Figure 2,will be installed to allow for the assessment of groundwater flow direction and gradient within that water bearing zone.To assess groundwater flow direction and gradient under the proposed surface impoundments, piezometer PZ-1 will attempt to be installed to the west of the surface impoundments as illustrated in Figure 2. However, given the distance from MW-35 and MW-35R,the first water bearing zone at PZ-1 may not be consistent with the first water bearing zone detected at MW-35R. In that case,the soil boring drilled at PZ-1 will be abandoned and another attempt will be made at the PZ-1 contingency location illustrated on Figure 2. Terraphase Engineering Inc. Page 3 of 6