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August 1994 -3- 933-2713.003 <br /> 3.2 Interpretation and Discussion of Geologic Data <br /> The geology along cross sections A-A' and B-B' is presented in Figures 2 and 3, respectively. <br /> The horizontal scale is at 1 inch = 20 feet for section A-A' and 1 inch = 40 feet for section B- <br /> B'. To the east of the creek, the area is capped by a layer of fill material ranging in thickness <br /> from several feet to 40 feet. The fill generally consists of clayey gravel and remnants of the <br /> original mill. Directly below the fill lies a sandy gravel zone. The sandy gravel zone was <br /> generally evidenced by poor core recovery and by the presence of sand washing up in the <br /> circulation water used for coring. Below the sandy gravel is a distinctive clayey gravel zone. <br /> Boreholes BH-5 and BH-6, drilled along cross section A-A', encountered a 10-foot thick clay <br /> layer sandwiched between two clayey gravel layers. Because the clay layer provides a lower <br /> limit for the conjunctive flow study, BH-5 and BH-6 were terminated prior to reaching bedrock. <br /> Figure 3 indicated that the top of the sandy gravel zone in borehole BH-3 was encountered <br /> approximately 20 feet higher than in neighboring borehole BH-2. The significant elevation <br /> difference of the sandy gravel zone between these boreholes suggests that the sandy gravels <br /> should be treated as two separate units, as shown in Figure 3. Hydrogeologic data discussed in <br /> Section 4.1.1 confirms that these two sandy gravel zones are distinct from one another. <br /> Latite bedrock was exposed on the west side of Cement Creek along Section B-B'. The latite <br /> bedrock appears to slope easterly. In cross section B-B', the latite bedrock was encountered at <br /> elevations 10,523, 10,516, and 10,467 feet in Boreholes BH-1, BH-lA, and BH-2, respectively. <br /> In cross section A-A', latite bedrock was encountered at elevation 10,528 feet in BH-4. <br /> Borehole BH-3 was terminated in Ferricrete (iron oxidized sands and gravels) at elevation <br /> 10,480 feet. Discontinuous zones of Ferricrete were also encountered in BH-4 and BH-1. <br /> Golder Associates <br />