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Transit Mix Concrete Co. <br /> Groundwater potentiometric elevation data can be used to develop an understanding of <br /> groundwater flow gradients, the general direction of groundwater flow, and rates of flow, both <br /> laterally and vertically. Groundwater flow through the subsurface rocks is from higher potential <br /> to lower potential, although the actual pathway and rate of flow is dictated by the hydraulic <br /> characteristics of the rocks. In the granodiorite rocks, groundwater flow is entirely through <br /> interconnected secondary fractures,joints and faults, so the pathway of actual flow may be quite <br /> tortuous, but the general direction of flow will be driven by the direction of the potentiometric head <br /> gradient. <br /> Differences in potentiometric elevations with depth at individual monitoring installations indicate <br /> the direction of the vertical component of the hydraulic gradient, as summarized in Table G-9. <br /> Also shown on Table G-9 is the calculated vertical hydraulic gradient, which is the potentiometric <br /> head difference divided by the depth difference where the head measurements apply. By <br /> convention, positive hydraulic gradients indicate downward flow, and negative hydraulic <br /> gradients indicate upward flow. <br /> Three multi-level groundwater monitoring installations, GW 2, GW 6 and GW 7, are located east <br /> of the West Fault within the Little Turkey Creek valley bottom. Potentiometric data from these <br /> locations indicate downward hydraulic gradients with shallow groundwater levels significantly <br /> lower than Little Turkey Creek. This indicates that Little Turkey Creek acts as a source of <br /> recharge to underlying groundwater in the eastern part of the Ranch property. This interpretation <br /> is supported by flow measurements taken during periods of minimal surface water runoff, that <br /> show a steady diminishing flow in Little Turkey Creek to the east of the West Fault. <br /> Groundwater monitoring installation GW-5, located about 1,500 ft. south of Little Turkey Creek, <br /> also shows a downward vertical hydraulic gradient component, indicating an area where <br /> groundwater is being recharged by infiltration of precipitation. <br /> Negative potentiometric level depths below the top of casing (the measurement datum) in <br /> Table G-9 indicate that hydraulic heads at this depth are above ground surface and result in <br /> upward hydraulic gradients at these locations. The upward vertical hydraulic gradient component <br /> shown at installations GW-1, GW-3 and GW-4 indicates areas of potential groundwater discharge <br /> to Little Turkey Creek surface water flow or to the ground surface within the Little Turkey Creek <br /> valley in the form of seeps. <br /> It should be noted that upward vertical hydraulic gradients at these locations are fairly high, <br /> ranging from 0.07 to 0.2, so that while hydraulic heads at depth are significantly above ground <br /> surface, hydraulic heads at shallow depths at these locations are typically close to ground level. <br /> This indicates that there is a significant loss in potentiometric head as the groundwater moves <br /> upwards from depth. The head loss is a reflection of the interconnection of the fracture system <br /> which results in a fairly high resistance to groundwater flow. As a result, where ground water <br /> discharges to ground surface, it is in the form of seeps rather than flowing springs. <br /> Hitch Rack Ranch Quarry Permit Application <br /> October 3,2017 G-31 <br />