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9 The seed mix used was composed primarily of introduced forage grasses, with two legumes, Alfalfa and Cicer milkvetch, which provide a suitable pasture mix for cattle. Limited patches of Canada thistle (Cirsium arvense) are concentrated in the drainages and wetter seep azeas. Colorado Yampa Coal Company has conducted annual chemical weed control. Occasional incidents of White top (Cordaria drabs) have been managed with chemical controls at Mine No. 2 as well. The presence of these weedy species is not extensive nor does it inhibit the post-mining land use. Sampling data from 1995 shows that 0.61% of the total cover in the East Block was attributed to noxious weeds, while noxious weeds in the West Block accounted for 0.30% cover. The commitment for establishment of species diversity in the permit states that, "The species diversity standards for pastureland states that alfalfa shall not exceed 75% relative production and perennial grasses shall provide at least 25% relative production. Also no single species shall exceed 75% relative cover." East Block data from 1995 shows that the azea is dominated by Brome grass (Bromis inermis) which contributes of the relative cover 54.61 %. Data collected in 1995 from the West Block confirms the dominance of Brome grass at a concentration of 58.99%. Although diversity is not a determinant of Phase II success, the data indicates that the reclaimed area is achieving the diversity standazd. Colorado Yampa Coal Company provided site specific vegetative sampling data for the reclaimed and reference azeas to develop a single storm SEDCAD+ model to demonstrate that the reclaimed azea produces less sediment than in pre-mine condition. The results of this comparison indicate that the reclaimed slopes produce less sediment than the azea in a pre-mine condition, if it had a cover equal to the reference azea, which based on data submitted, is an acceptable assumption. Colorado Yampa Coal Company further supports this modeling result with the general lack of erosion and the presence of permanent livestock ponds to enhance the post-mine land use of pastureland. Observations of Division inspectors in the field substantiate the lack of erosional features throughout the Mine No. 2 site. Only minor rilling was encountered in limited locations. The overall sediment yield is less than similar, un-mined adjacent azeas. The Division finds that Colorado Yampa Coal Company has met the requirements for Rule 3.03.1(3)(b) for Mine No. 2. Pond M and its collection ditches, ditch M-I and M-3, have been approved to remain as permanent structures via Technical Revision No. 37. Pond M will serve as a livestock pond to support the post- mining pasture use. One other permanent livestock pond remains in the requested bond release azea. This is pond 6-a, located in the East Block. This livestock pond has been certified and demonstrations made in accordance with Rule 4.0.9(1). Livestock pond 6-a is located up slope (South) of permanent drainage PG 6-2. Seven other livestock tanks exist throughout the Mine No. 2 area. These aze outside of the current bond release azea and have either been released previously, aze located outside the disturbance azea, or in the case of Livestock pond U-g, existed prior to the mining operation. These livestock ponds are identified as U-b, U-a, N-d, N-c, Pond O, Pond P, and U-g. Pond K is required to be removed upon successful suspended solids demonstration (Rule 3.03.1(3)(b)). The surface landowner over the majority of the proposed bond release block is Colorado Yampa Coal Company. Colorado Yampa Coal Company continues to operate a