2011-09-19_REVISION - M1982155 (17)

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distinction being slightly higher in organic matter. Nevertheless, the slight difference is significant for revegetation. The overburden will be spread first. As previously discussed, initial material balance estimates suggest that overburden material may not be sufficient for slope backfilling and pit bottom cover. At most, no more than a couple feet of overburden will be available to top -dress the final pit bottom. The worst case scenario is that the pit side slopes will be created using a "cut and fill" approach, and the side slopes and pit bottom will be top- dressed with a couple feet of overburden prior to final topsoil application. The topsoil will not be placed evenly over the entire site. The floor of the pit will likely need little or no topsoil because moisture accumulation there will likely create a rapid soil development with the overburden. Therefore, the soil will be used to a minimum depth of four inches on the slopes. It is likely that more depth can be used than the minimum, but not knowing exactly how much topsoil will be generated in the stripping, a four inch minimum is used. Since the topsoil will go on top of a considerable depth of overburden, the total plant growth medium depth will be on the order of at least a foot and often two feet or more. When topsoiling and spreading overburden on slopes, the same requirements as for general grading are needed. That is, final fine grading prior to seeding will only follow the contours of the slope and will never produce tracks up and down the slope. Revegetation Planting of the site will be done as areas are finished with preparation after grading and spreading overburden and topsoil. Planting will be most successful if done between the end of November and the end of February. Planting, if need be, can be done in March but after March it is not advisable to plant on this site. Planting before the end of November is also ill advised as the growth environment will be warm and early germination would likely result in a major failure of the revegetation and require reseeding. On this site, broadcast seeding is not advisable as seed burial would be limited. Seed coverage can be accomplished after broadcasting if the surface is very loose, such as occurs immediately after spreading the plant growth medium. If the seed is broadcast in those circumstances, then the seeded area will be dragged to help bury the seed. This may be necessary on side slopes since drilling on the slopes may be unpractical. No mulch or fertilizer will be applied. On west and south facing slopes, mulch can be applied if desired, but only if the mulch is very strongly crimped into the soil. On this site, straw mulch, unless well anchored would most likely just blow away providing in little benefit. Fertilizer will not be applied at the time of seeding because fertilizer tends to benefit annual weed growth which can result in excessive competition for precious moisture and seeding failure. Fertilizer, if used at all, will only be applied in the fall of the first and /or second growing season. Fertilizer then will benefit the grass growth without increasing weed growth significantly. However, any fertilization should be done using a method that does not cause large scale disturbance of the surface. Preferably, it should be done by hand. Extensive redisturbance will only encourage weed growth. Using the designated species in the seed mixture should not require fertilization Fountain Pit M- 1982 -155 DRMS 112 Permit Amendment Page 13