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• of the fill. <br />3. No springs or seeps have been noted on the face of the Fill or associated with construction <br />of the Fill. Prior to construction of the rock underdrain, during clay and soil removal, a minor <br />perched zone of water was encountered adjacent to the canyon bottom. A lateral drain connected <br />to the main underdrain was constructed to ensure that the water is routed efficiently away from the <br />Fill. Flow from the area remains less than five gallons per minute and is routed to the West Pit <br />Pond. The lateral drain is located down gradient from the piezome[er well and, as such, has no <br />appazent effect on the piezometer well. <br />During the spring of 1998 it became apparent that the second drainage bench (neaz the 7050 level) <br />had settled in the area that corresponds to the original valley bottom. The bench was too flat and was <br />not performing according to the design. The north end of the bench neaz the confluence with the <br />rock surface drain was lowered about 12 feet and tapered to the south to reestablish the correct grade. <br />The azea was graded, re-topsoiled and seeded during the fall. No further problems with the drainage <br />bench aze anticipated. <br />In summary, during 1998 the construction of the West Pit fill proceeded according to the plan. [n <br />addition, the monitoring suggests that the Fill is performing as designed. <br />• <br />• <br />