Laserfiche WebLink
18 <br /> 16 <br /> v <br /> 14 <br /> u_ <br /> H 12 <br /> a <br /> c <br /> Y <br /> 1110 <br /> W 8 <br /> R <br /> 3 <br /> R 6 <br /> V) <br /> E <br /> 3 4 <br /> 3 <br /> a2 - - -- - -- -— -- <br /> 0 <br /> 0 500 1,000 1 500 2.000 <br /> Distance from Edge of Pit (feet) <br /> Figure 3. Estimated Groundwater Drawdown from Edge of Dewatered Lakes <br /> 4.0 POTENTIAL SLURRY WALL IMPACTS <br /> Once a slurry wall liner is constructed around an existing groundwater lake, impacts to the <br /> adjacent groundwater table from lake surface evaporative losses and/or pit dewatering will cease. <br /> The lined reservoir will influence alluvial groundwater flow near the slurry wall, but these <br /> influences are typically localized. As described in Section 2, groundwater conditions at the <br /> Lamb Lakes property are generally similar to most alluvial aquifers along the Colorado Front <br /> Range; exhibiting significant transmissivity and low gradient. Groundwater flow is in the same <br /> direction as, and towards, the river (see Figure 2). The alluvial groundwater elevation and flow <br /> direction in these systems are typically influenced by fluctuations in river flow, direct <br /> precipitation and infiltration, agricultural irrigation, and withdrawals from water wells. <br /> Mounding and shadowing refer to a slightly higher or lower normal groundwater elevation, <br /> respectively, and can be caused by obstructions to the natural alluvial groundwater flow regime. <br /> Once a slurry wall is complete, and based on the estimated groundwater flow regime, mounding <br /> is anticipated west and northwest, or upgradient, of the slurry walls and shadowing is expected <br /> east and southeast, or downgradient of the reservoirs. Although it is difficult to quantify exact <br /> elevation changes, these groundwater elevation effects are expected to be most pronounced <br /> immediately adjacent to the slurry walls, with groundwater returning to normal elevations over <br /> ..- Page 9 of 12 <br /> blue earth <br /> SOLUTIONS <br />