COMPLIANCE INFO_PR0440063_1990-2019

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Musco Family Olive Compan - 3 - 27 July 2006 not extend into any confining layers that overlie or underlie the unit to be monitored, unless otherwise approved by the enforcing agency. The annular surface seal shall be no less than 20 feet in length. Seal lengths less than 20 feet are permissible only if shallow zones will be monitored and approval has been obtained from the enforcing agency. If possible, special protection shall be provided where a reduced-length seal is used, as described in Section 8 of the Water Well Standards. • According to Department of Water Resources (DWR) California Well Standards Bulletin 74-90, Part 11 Monitoring Well Construction, Section 9, C: Radial Thickness of Seal: A minimum of two inches of sealing material shall be maintained between all casings and the borehole wall within the interval to be sealed, except as noted in Section 9 of the Water Well Standards. At least two inches of sealing material shall also be maintained between all "casings"in a borehole, within the interval to be sealed unless otherwise approved by the enforcing agency. Additional space shall be provided, where needed, to allow casings to be properly centralized and spaced and allow the use of a tremie pipe during well construction (if required), especially for deeper wells. Based upon information provided for well W-2, it is apparent the installation and design of well W-2 does not meet the standards in accordance with ASTM D5092 (industry standard) nor DWR well standards (State Standard). The use of a 6-inch diameter auger with a 4-inch diameter well casing does not provide adequate annular space as required nor is the sanitary seal constructed to the minimum 20 foot length. Furthermore, well W-2 is not in compliance with Title 27, Section 20415(4) Monitoring Well Performance Standard, that states: • (B). The sampling interval of each monitoring well shall be appropriately screened and fitted with an appropriate filter pack to enable collection of representative ground water samples. • (C). For each monitoring well, the annular space (i.e. the space between the bore hole and well casing) above and below the sampling interval shall be appropriately sealed to prevent entry of contaminants from the ground surface, entry of contaminants from the unsaturated zone, cross contamination between portions of the zone of saturation, and contamination of samples. In addition, well W-2 has not yielded groundwater samples since October 2004 and is therefore out of compliance with WDR No. R5-2005-0024, as stated in Finding #27: • If specific wells that monitor the Units remain dry over four consecutive seasonal sampling events, the Discharger shall be required to propose additional wells to comply with ground water detection monitoring requirements.