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of 12 feet would require that from 20Y. to 40% of everything mined go back on the benches. That is not acceptable or possible. We have proposed placing suitable amounts of fill on the benches to establish grasses, shrubs, and eventually trees. We believe that through the growth of trees along the wall faces much of the wall pattern will eventually be obscured and safety improved. Furthermore, with a 50 foot wide bench and IB feet of fill, you cannot achieve a 3:1 slope. Which leads us to the next subject. In our opinion, having the proper depth of fill to accomplish the revegetation and the proper slope to control erosion is more important that having a 12 foot wall. It mould be nice to have it all, but if a choice must be made between having a 20 foot wall or a 4:1 slope, we will apt for the 4:1 slope with adequate fill depth. We mention a 4:1 slope because in our opinion the revegetation of a 3:1 south facing slope is extremely difficult. The insolation angles during most of the summer will be nearly vertical, whereas a 4:1 slope will have from 8 to 10 degrees less insolation angle. With mid-surmier sun intensity like that, a 10 degree difference in the insolation angle can mean the difference between success and failure. ITEM 12 - You have stated that you intend to plant tree seedlings along the tops of the backfilled slopes, adjacent to the backwall. The May 5, 1989 Colorado Division of Wildlife letter has recommended that trees be used sparingly. What will the tree planting density be? What is your estimate for the total number of trees in the Phase III area. What will the average seedling size be? Can any existing tree saplings be transplanted far use along these backwalls. RESPOVg: We are in a Catch 22 here. The DCiJ wants few trees; the public wants lots of trees. We have opted for the DOW plan because the primary final land use is for wildlife. The trees will be planted in the deeper backfill near the walls to provide for plenty of room for root growth. We feel that a planting distance of about 20 feet apart is about right to allow for adequate growth without crowding and excessive moisture competition. Keep in mind that Pinyin Pine, the tree to be planted the most, has a very spreading root system. We cannot determine how many trees will be planted because it cannot be determined exactly how many benches will be produced. That can only be determined during the mining. As a rough guess though, it will probably be somewhere between 200 and 400 trees. The seedlings will be acquired from the Colorado State Forest Service and will be their standard potted stock which is usually about 12" tall. Transplanting small trees can be done, but it is probably not worth the effort because survival is so low. Furthermore, removing even a small tree from such a rocky soil wfiere many major roots have grown into bedrock cracks presents considerable problems in the avoidance of damage to the root system, not to mention exposure to excessive air, which is a sure way to kill a transplant. ITEM 13 -_ t?i page 41, regarding the staining of the unreclaimed walls, it is stated that "tests are planned to determine whether this staining can be applied here at a low cost and with comparable benefits. Have these test occurred? Where? What are the results? 4hat are the impacts to surface water quality by using these paints? What will be the impact to any vegetation in close proximity to these paints? Are these paints in any way harmful to wildlife? SM'DER NW AhII~hETJT ADEC1lYlCY RESPQ~S MAY 22, 1989 PA(~ 11