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The spring and early to mid-summer of 2000 was unusually dry and hot. Little <br />precipitation and extremely hot days were experienced throughout the region during this <br />period of time. As a result, soil moisture was extremely low. It is assumed that the low <br />soil moisture content was exasperated on the mine bench outslopes by the lack of mulch <br />cover. <br />The five outslopes which were revegetated in 1999 were cazefully monitored on a <br />number of occasions during the summer and fall of 2000, and annually on a periodic <br />basis through the 2003 growing season. During 2000, some germination was observed to <br />occur on each outslope as the summer progressed. The effects of the weather pattern <br />could be observed to take a significant toll on the immature plants, however, as many of <br />the grasses which had emerged as seedlings had died by mid-August. This observation <br />was consistent at four of the five outslopes. These four slopes all have a south to <br />southeast aspect, exposing them to the summer sun throughout the day. The lone <br />exception to this pattern was the north facing outslope at Mine 3. This area experienced <br />more significant germination. <br />These observations indicated that the lack of moisture and exposure to the sun as a result <br />of mulch removal in the fall of 1999, and throughout the 2000 growing season, severely <br />impacted the expected germination rate, and thus the potential revegetation success, at <br />most of the mine bench outslopes. However, the growth evidenced at the north facing <br />slope at Mine 3 indicated that the technique used was viable, and could be mimicked, <br />with some modification to accommodate climatic conditions and soil moisture retention <br />characteristics. <br />Because the Division believed that the methodology was sound, it was determined to <br />make another attempt to stabilize the slopes through revegetative processes. However, to <br />accommodate the severe drought and climatic conditions in Coal Basin, certain <br />modifications to the revegetation methodology were indicated in order to improve the <br />moisture holding capability of the mine bench outslopes, and to maintain the protective <br />mulch cover. <br />The conceptual improvements included: <br />- Increase the number of constructed shelves per acre by ten percent to increase <br />germination potential; <br />- Aerially apply a liquid tackifier such as guaz-gum or "Earth Bound" to the mulch <br />to increase the life span of the mulch on the slopes; <br />- Plant trees on the slopes to help reduce mid-slope surficial soil creep; <br />- Increase the number of shrubs using more mature plants, at the base of some <br />outslopes to increase the effectiveness and shorten the length of time necessary to <br />establish effective natural sediment barriers. <br />