Laserfiche WebLink
0 <br />• that is placed in a valley where side slopes of the existing valley measured at the <br />steepest point are greater than 20° or the average slope of the profile of the valley from <br />the toe of the fill to the top of the fill is greater than 10°." Based on our estimates the <br />classification of the excess spoil areas is shown on Fig. 1. <br />Sedimentation Pond Embankments <br />Proposed embankment locations are shown on Fig. 1. Plans were revised at <br />several locations during our investigation to relocate and reduce embankment heights. <br />We understand the embankments do not meet jurisdictional criteria of the State of <br />Colorado or MSHA. Based on information provided by Greystone, the dams have a <br />maximum 10 feet height, with 2.5:1 outslopes and decant outlet pipes. <br />Contour Mining <br />Contour mining is planned in Lorencito and Little Jeff Canyons. Backfilling with <br />spoil to approximate original contours is planned. Height of these slopes will typically <br />be on the order of 50 feet or less, with a maximum height less than 100 feet. Backfilling <br />of contour mine areas to 2.5:1 slopes will not allow re-establishment of approximate <br />original contours where the existing ground is steep. <br />Locations of proposed excess spoil disposal areas and sedimentation ponds are <br />shown on Fig. 1. The fill areas are relatively small and are predominately sidehill fills <br />with the exception of Fills 2-1 and 8-1. <br />SITE CONDITIONS <br />This section describes our understanding of conditions regarding geology, <br />topography, landslides and seeps. <br />• LORENCITO COAL COMPANY, LLC <br />LORENCITO SURFACE MINE - PNASE 1 <br />CTLrt 32, 611 <br />4 <br />