COMPLIANCE INFO_PR0440063_1990-2019

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Musco Family Olive Compano - 2 - 11 January 2008 the underlying geologic material is of a fine-grained nature, and there is an approximate 30 foot difference in hydraulic head between the two deep zones. 7. Contouring the two deep well sets in Findings #4 and #5 indicates groundwater is flowing northeast beneath the Musco factory and Class II Surface Impoundments. 8. Using groundwater elevation data from well MW-8 causes an apparent northwest component to groundwater flow. 9. According to the report, Musco suggests there is not enough resolution to accurately depict the groundwater flow regime. 10.Well MW-2 and MW-25 appear to be monitoring similar, deep, water bearing zones of the Neroly Formation, which, based on the chemical data, are much saltier compared to the upper water bearing zones monitored at the site including the two deep groundwater zones identified beneath the Musco factory and Class II Surface Impoundments. 11.The anomalous groundwater found in wells MW-2 and MW-25 appears to extend southwest of the site where the Neroly Formation has been mapped. It is staff's opinion the high concentration groundwater is located at depth in a confined to semi-confined aquifer. 12.Staff has discussed with Musco and consultants a pump test of well MW-2 to evaluate hydraulic communication with the shallow wells located in the uplands area. Musco, however, has not proposed to conduct this type of test. Staff recommends Musco propose a method to determine whether hydraulic communication exists between the water bearing zone wells MW-2 and MW-25 and the wells monitoring the shallow water bearing zone of the uplands area monitored by wells MW-1, MW-3, MW-13 through MW-16, and MW-23. Musco should evaluate the test method in the 15 February 2008 work plan report due under Cease and Desist Order No. R5-2007-0139. Staff requested in its 15 December 2006 Review of Groundwater Quality and Hydrogeology Memo that Water Quality Protection Standards (WQPS) be developed for background monitoring wells installed during the 2007 construction season. Based on the data collected to date, staff concludes that well MW-24 adequately represents shallow background conditions of the Musco property. A deep zone background well was'not installed during the 2007 Phase I drilling activities. In the Memo, staff requested Musco collect a minimum of eight water samples to be used in a statistical analysis to develop background concentrations. This analysis was to be submitted by 31 January 2008 in the 2007 Annual Monitoring Report. Based on the number of current samples collected, Musco has only collected two of the eight samples from well MW-24. However, depending on the statistical method.used, the number of samples collected through the end of 2007 might suffice, since concentrations of constituents of concern do not appear to vary significantly. Staff requests Musco include the concentration limits pursuant to Section 20400 of Title 27 for well MW-24 in the 2007 Annual Report, which is due 31 January 2008. If