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10/5/17 <br /> Mr. Montgomery, USACE <br /> Page 5 of 12 <br /> the dragline method the sand and gravel was excavated underwater with the dragline bucket <br /> and cast to stockpiles at the side. Using that method the water level in the ponds could <br /> remain high and the groundwater flow largely uninterrupted. In the new method the pit water <br /> is pumped down to a level where mobile equipment such as rubber tired loaders can <br /> excavate the alluvial sands and gravel. Accordingly, the water level has to be drawn down <br /> several tens of feet; and most importantly, well below the level of the South Pond of the Love <br /> Pit wetlands across the highway. <br /> Concern A—Groundwater Supply to the South Pond Durino Operations and After Closure <br /> During 2017, Everist has pumped water to a ditch along the west side of Highway 9 <br /> at the approximate location shown on Figure 1 in an attempt to recharge the groundwater <br /> flow eastward beneath Highway 9. That has worked to a degree, and has kept the water <br /> level in the South Pond within a few inches of the levels observed in 2004. The two pages of <br /> photos that are attached show exposed cobbles along the shore-line that were previously <br /> submerged. However, the upwelling flow into the marsh along the southern shore of the <br /> South Pond has not been a continuous supply. <br /> Photo 9 - South <br /> Pond Area August <br /> 31, 2017 (Photo <br /> provided by O'Hara, <br /> Everist Materials) <br /> � � </'� � ��� % ��p�� � ✓ice <br />