2018-05-30_REVISION - M1983035 (3)

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polyacrylamide additives in the vicinity of the root ball. The pines have survived by virtue of the high drought tolerance of pinyon, but most of the spruce died, in spite of an irrigation system being used to establish the trees. That species normally grows at and above about 3,500 to 4,000 feet higher than this site - no wonder they died. In the reclamation,the irrigation piping will need to be removed as well as many of the trees. And the root balls of the trees may present a difficulty in the removal of the material for topdressing in the reclamation. The volume of material in this berm is unknown and would be very difficult to even calculate as the south side of the berm has a slope that varies from 4:1 in a few places to nearly 1:1 on the west end and a lot of variability in the cross-sectional shape of the berm, including one significant bench on part of the berm's south face. Suffice it to say,that this berm appears to contain most or all of the material that was removed prior to mining. Therefore, removal and redistribution should be able to top dress the pit disturbance rather nicely and possibly even fill in some deeper depressions, if desired. The southern berm is a much more sensible structure and appears to have been constructed with an idea that it would remain after reclamation. This berm is composed of two connected parts. The easterly connection that runs along the south permit boundary but well beyond the current disturbance is an effective, low profile barrier that keeps runoff from going south. It gets taller to the west where it joins the east/west portion of the southern berm and basin adjacent to mined land. This is useful now because of development of the land to the south of the berm. As discussed previously, it protects that development from huge flows as a result of very large thunderstorms. The Palmer Divide and areas a short ways north and south of the divide are noted for having tropical hurricane-like thunderstorms that, in one case, discharged 24" of rain in 24 hours and most of that fell over 4 hours (Elbert, CO in May 1938). Storms south of the divide have never been that large,but 12" to 16" in 24 hours or less is not unheard of. However,the far eastern part of the berm has an adverse effect in that it directs runoff to the southeastern corner of the mined area which has been affected by some fairly severe and expanding headward erosion into unmined land. That then drains into the basin on the north side of the western part of the berm. The eastern end of the portion of the berm adjacent to the mined land is unfinished and has steep, eroding slopes. The berm that forms the south edge of the mined area then curls around the western side of the pit to the point where the access road enters the operation. For the most part,the vegetation on the finished portions of this berm, from top to bottom, is in good condition mainly due to it being north facing. The southern side of the berm, although hotter and drier,does not have bad vegetation cover; it is just not very good and is rather weedy. The slope down into the deeper pit on the Vollmer Pit Technical Revision June 2018 Updated Reclamation Plan Page 4 of 26