Laserfiche WebLink
Anderson-Barng rover Ranch, Linden - 2 - 22 September 2023 <br /> 4. Brusca concludes that the extent of soil impact at the Site is reasonably well <br /> characterized, and that Site conditions meet LTCP Direct Contact and Outdoor Air <br /> Exposure criteria because shallow soil concentrations are below LTCP Table 1 <br /> thresholds. Central Valley Water Board staff concurs. <br /> 5. Brusca states that the extent of petroleum impact to groundwater west of the Site <br /> is adequately defined. While the boring west of the walnut huller building (TH10) <br /> did contain hydrocarbons, the concentrations were three orders of magnitude <br /> lower than those in boring TH9. As such, Central Valley Water Board staff <br /> concurs that the extent is adequately defined to the west. <br /> 6. Brusca states that additional assessment of the extent of petroleum impact to <br /> groundwater is needed south of the Main WSW. Brusca proposes one additional <br /> boring approximately 130 feet south-southwest of the Main WSW, which is <br /> located approximately 120 feet south-southwest of the former UST. As the boring <br /> TH9, approximately 20 feet from the Main WSW, contained 6.7 million <br /> micrograms per liter (ug/L) diesel range organics (DRO), Central Valley Water <br /> Board staff concurs that additional assessment is needed to delineate the extent <br /> of groundwater impact to the south. However, to properly define the plume, two <br /> additional borings are needed west and east of the Main WSW. Central Valley <br /> Water Board staff requests that you complete the three borings with the same <br /> methodology as previous borings TH7 through TH9, with no work plan required. <br /> Central Valley Water Board staff requests that you submit a Site map with <br /> proposed locations for the two additional borings for staff concurrence prior to <br /> commencing with field work. <br /> 7. Brusca recommends resampling the Main WSW to confirm that it remains <br /> unimpacted by the Site release. Central Valley Water Board staff concurs. <br /> 8. Central Valley Water Board staff requests that by 6 October 2023 you submit a <br /> Site map with proposed locations for the two additional borings for staff <br /> concurrence. Central Valley Water Board staff requests that by <br /> 22 December 2023 you (1) re-sample the Main WSW, (2) complete the three <br /> additional borings and sampling, and (3) submit an assessment report. In this <br /> report, please re-evaluate LTCP General and Groundwater criteria. <br />