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CDCR Remedial Design UpdateField Program:Step testing and constant rate conducted on both EW-1 and PZ-2.Geological/Hydrogeological Interpretation:The hydraulic testing also backed the <br />geological interpretation of a heterogeneous environment, with marked <br />differences in the hydraulic response between EW-1 and PZ-2. <br />Well Capacities: <br />o EW-1 step testing indicated a capacity range in the region of 0.6 to 1 gpm. <br />This reflects the silty sands / sandy silts observed in the screen interval. <br />o PZ-2 step testing indicated a capacity range in the region of 5 to 10 gpm. <br />This reflects the silty sands with some gravel intervals in the screen <br />interval. The gravels are dominating the hydraulic response, and ultimately <br />likely will dominate COC flow. <br />ROI:Constant rate testing only indicted tenths of a foot influence on neighboring <br />wells at rates up to 2 gpm. This likely only indicates several to tens of feet <br />capture. Higher ROI would require well installations in higher permeability <br />materials and greater extraction rates, likely 10s of gpm. <br />COC Distribution Interpretation: COC concentrations from preliminary samples <br />prior to hydraulic testing indicated that the COCs were bound / located more in <br />the finer sediments and/or eastward direction, as EW-1 and PZ-1 had higher COC <br />concentrations and PZ-2 about half. PZ-02 had significantly greater thickness of <br />gravels. <br />Ongoing Remedial Design:For this design due to the heterogeneity in lithology <br />additional geological investigation is required prior to additional remedial design <br />considerations and/or installations. <br />PZ-2 Step Testing Interpretation <br />PZ-2 Test Duration: <br />•Step Test: 8 hrs <br />•Constant: 12 hrs