COMPLIANCE INFO_PR0440063_1990-2019

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Musco Family Olive Compan - 3 - 6 March 2008 Staff approves the Phase II well installations with the modifications noted above and described in more detail here. As discussed in the 30 January 2008 staff letter responding to the proposed Phase II groundwater investigation, staff had requested one shallow well south of the Safeway Distribution Center located in the vicinity of the terminus of the surface stream emanating from the Musco property. Instead of adding an additional well, staff would prefer to have well cluster#2 (shallow and deep) moved southeast, toward the terminus of the surface stream emanating from the Musco property. Staff requests Musco convert the proposed Canal Influence well into a well cluster (shallow and deep). The objective of this additional well is to provide better triangulation for groundwater flow direction and water quality analyses of the deep zone. Staff requests Musco consider an additional Deep Well (PDW4) to be installed in the vicinity of well MW-22. This well location would provide further understanding whether deep, confined, high-salinity groundwater is moving in an upward direction and mixing with the overlying groundwater in the lowland area. In addition to the above comments, staff requests the following: A qualified field geologist under direct supervision of a Professional Geologist must log all borings drilled during the Phase II Groundwater Investigation. The geologists cannot be employees of Musco Family Olive Company or its affiliated companies. • All deep wells targeting high salinity water be constructed with conductor casing to ensure upper water bearing zones are isolated from the pressurized aquifer systems typical of these wells (e.g., MW-2 and MW-25). • A minimum of one deep boring from each Study Area is continuously cored to provide complete lithologic logging of the subsurface. Since the intervals of interest are relatively deep, continuous cores of the boreholes can begin approximately 25 feet bgs. Perform borehole geophysics on all wells PDW1 through PDW4 and all other proposed deep wells from each study area, including Boring #4. Boreholes advanced to first encountered groundwater should be overdrilled to better define the thickness of the aquifer. The overdrilling should be terminated when the water bearing stratum has been fully penetrated. Deep zone wells located in Study Area 1, 2, and 3 should target a drill depth that coincides with first encountered deep-water onsite. This should be between 110 and 115 bgs. • Future cross-sections need to include the 84-million gallon reservoir location and surveyed depth in profile. The Discharger should include the reservoir water level in profile when preparing the cross-sections. In accordance with Cease and Desist Order (CDO) No. R5-2007-0139, the Phase 11 Well Installation Report is due 15 July 2008. Also in accordance with the CDO, the required Water Quality Protection Standard Report is due 31 March 2009. Regarding the 31 January 2008 letter from Musco to the Executive Officer, Regional Water Board staff awaits the submittal of the reports required by the CDO for establishing the WQPS. Staff continues to assess the content and conclusions of the Phase I report and Phase 11 work plan in terms of eventual compliance with the CDO. Additional discussions with you will clearly be necessary as the Phase 11 work proceeds and more data becomes available.