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-top width of at least 10.0 feet. - sideslopes of 2.5H:1.OV on both the outer and inner slopes. -high compaction due to the material and equipment available on site. - a principal spillway pipe and an emergency spillway cutout in the dam. A cross-section of the typical pond is shown on Drawing 1 of this report. In the amendment area ponds, a keyway will be dug at the bottom center of the embankment for added stability, although this keyway will not be assumed in the analysis to be conservative. Also, the cross- section used for the analysis shows adownward-sloping original ground surface away from the embankment. This is conservative since all the ponds except for Pond 010 have a mild original ground surface. 2. Foundation and Embankment Material Characteristics By examining the pond locations and the soils map, it is apparent that the material for embankment construction will be either two types: 1) Those subsoils with coarse fragments (soil unified classification types GC or GM). These are soils 98B, 98C, 98D, 98G or 98H as shown on the soil inventory map of the permit. Table 1 on the following page shows that these soils are either poorly graded gravel-sand-silt or poorly graded gravel-sand clay. 2) Those soils without coarse fragments (soil unified classification types SM-SC or SC). These are soils 98D, 98E and 98F as shown on the soil inventory map of the permit. Table 1 on the following page shows that these soils are either poorly graded sand-clay mixture or sand-silt- clay with slightly plastic fines. The material for the foundation will consist of the natural subsoils which are currently being stripped by scrapers and replaced in the backfill. This material is also poorly graded, will have coarse fragments and is classified as a GC soil -poorly graded sand-gravel-clay or GM -poorly graded gravel, sand & silt. • (Revised 72/00) Attachment 2.05.3(3) -10-110