SITE INFORMATION AND CORRESPONDENCE

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Ms. Anne Ogrey • •-2 - 19 August 2008 Holly Sugar-Tracy plume is defined. The Second QMR concludes a reasonable timeframe and that the QO of 100 Ng/L in about 20 years. Regional that the groundwater will reach the W Water Board staff does not agree. The attached concentration graphs for each of the three wells t the Site not clear how Spreckels can determine increasing ne when the Site will reach ach WQOs when thereliss no declining trend in Site wells. 2. Spreckels also needs to show that the groundwater plume is delineated prior to closure. Concentrations in downgradient monitoring wells MW-FO-2 and MW-FO-3 are increasing. The Work Plan recommends installing one well near the location of soil boring FOP-1 R, but does not include any additional wells to define the downgradient extent of the plume. By 15 September 2008, s needs to submit a revised plan to define the lateral extent of he plume, includingl downgradient of MW-F02 and rk MW-F03. 3. On page 2, the Work Plan refers to Figure 1, but there is no Figure 1 in the Work Plan. The Work Plan does include a figure labeled Figure 3 Approximate Monitoring Well Locations (July 2005), but this figure does not show the location of the proposed well near FOP-1R. Also, the north arrow is not up so Regional Water Board staff statements regarding defining the plume to the east were mistaken since FOP-1 R is to the south of the AGT. Spreckels needs to ensure that all figures are properly labeled and included with the reports. By 15 September 2008, Spreckels needs to submit a figure showing the locations of all proposed monitoring wells. 4. The Work Plan states that because of the high potential for false positive test results from grab samples taken in test holes, the test hole will be terminated if there is any indication of soil containing petroleum products. Spreckels proposes installing the monitoring well where no traces of petroleum hydrocarbons are visible in soil. It is unclear how Spreckels plans to determine the presence of petroleum hydrocarbons in soil. The purpose of the monitoring well is both to delineate the plume and to confirm the previous concentration at FOP-1 R. Spreckels needs to install one well near FOP-1 R regardless of the presence of petroleum hydrocarbons in soil. Spreckels must take careful measures to reduce the potential of dragging contaminated soil down to the groundwater, and once the well is installed, Spreckels must develop the monitoring well sufficiently to obtain a sample representative of Site groundwater. If Spreckels chooses to install an additional monitoring well further south of FOP-1 R where the soil does not contain petroleum hydrocarbons that is acceptable, but one well needs to be installed near FOP-1 R. By 15 September 2008, Spreckels need to submit a revised work plan clarifying that it will install a minimum of one well near FOP-1 R. 5. The Work Plan states that soil samples will be taken every two feet until groundwater is encountered. Spreckels needs to analyze these soil samples for petroleum hydrocarbons and submit the results. 6. The Work Plan states that the drill cuttings will be placed on top of the levees. Spreckels needs to contain all investigation derived wastes (IDW), collect samples, and analyze the samples to determine the proper disposal methods. Spreckels may not spread IDW on the levee.