COMPLIANCE INFO_PR0440063_1990-2019

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Musco Family Olive Compan - 5 - 27 July 2006 and not influenced by the higher conductivity gravel layer encountered between 82 and 80 feet, respectively. Overall, there appears to be good correlation between well borings MW-12, MW-17, and MW-18. Conclusions Based on this evaluation, it appears several of the wells associated with the Detection Monitoring Program (DMP) (W-2 and MW-11) are inadequate and do not meet the requirements of Title 27 or WDR No. R5-2005-0024. Wells W-2 and MW-11, when initially installed, were monitoring a perched water zone that has since dried as indicated by declining water levels. Well W-2 is supposed to be the point of compliance well for the southern end of the surface impoundments. Well MW-11 is supposed to be the furthest upgradient or background well for the surface impoundments. It is Board staff's judgment that first encountered ground water occurs at an interval between an approximate depth of 50 to 70 feet bgs. This judgment is based on correlating lithologies from boring logs W-2, MW-11, MW-12, MW-17, and MW-18 with additional information from logs W-1 and W-3. Currently, only one well (MW-17) appears to be installed at an appropriate depth to monitor shallow ground water beneath the surface impoundments. The current shallow well system (W-2, MW-11, and MW-17) does not adequately monitor the shallow ground water beneath the surface impoundments. Boring logs for deep wells MW-12 and MW-18 identify a stratum of highest hydraulic conductivity above deep ground water. This stratum was encountered at depths between 80 and 82 feet bgs. This zone of highest hydraulic conductivity is not being monitored. Therefore, the current deep well system for the surface impoundments is out of compliance with Title 27 and the requirements of the DMP. Board staff makes the following recommendations for the DMP: 1. Well W-2 was installed as a downgradient point of compliance well but has not yielded groundwater samples since October 2004. Construction and installation of well W-2 does not meet the ASTM, DWR, or Title 27 Monitoring Well Performance Standards. Well W-2 monitors a perched zone downgradient of the surface impoundments and shall remain in-place if the Discharger can provide a copy of the well permit from the authorizing agency. If a copy of the permit cannot be provided, the Discharger must drill out and reconstruct well W-2 to a corresponding depth monitoring the perched zone. Regardless of whether or not a well permit is available, the Discharger must drill and construct a companion well to W-2 to monitor the shallow groundwater zone identified between 50 and 70 feet bgs. The well boring should be continuously cored for logging purposes. The Discharger is required to reconstruct well W-2 and install a companion well. Both these wells shall meet the ASTM, DWR, and Title 27 Monitoring Well Performance Standards. 2. MW-11 was installed as an upgradient well at a depth to monitor the perched zone and should remain in place. The Discharger shall continue to monitor this well for depth to water and report their findings as required in the Monitoring and Reporting Program No.