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Colowyo's initial modeling assumptions reflecting upstream mining and reclamation practices were, unfortunately, rejected by the Division. In its place, the Division mandated that modeling assumptions be based upon a "worst case scenario" for the West Pit based entirely on topsoil stripping and ignoring upstream mining and reclamation practices. Colowyo believes that not only is the concept of modeling based upon a "worst case scenario" not supported by the CDMG regulations, but such a modeling exercise has little utility beyond the short window of initial topsoil stripping associated with a specific area. Once mining activities, such as in-pit road construction, overburden blasting and removal, development of spoil dump areas, etc. occur, modeling assumptions based solely upon initial topsoil stripping and high curve numbers (in the 90+ range) provide no utility with respect to subsequent activities of the mine. While Colowyo's other pit related sedimentation ponds can be viewed as structures designed to address the needs for controlling runoff from reclaimed areas for up to 30 years, the West Pit Pond design has limited intuitive utility as it was designed for a short time period measured in months during which initial pit development topsoil was removed. Not only did Colowyo disagree with the Division's modeling requirements, it became apparent that the Division's intent was to also attach an enforcement mechanism to the pond modeling exercise. While we do not believe the regulations intended that pond modeling should be utilized as an enforcement tool, Colowyo reluctantly accepted as a permit condition another Division mandate that, based upon the mandated modeling assumptions, a maximum of 124 acres of runoff and sediment would be allowed to flow to the West Pit Pond during initial topsoil stripping. It was absolutely necessary during the initial development of the West Pit to 1) provide for in-pit access ramps into the pit from the east pit and coal crusher, 2) prepare the west pit fill area for subdrain construction and the dumping of 16.5 million cubic yards of excess spoil and 3) strip topsoil from sufficient area for the shovel to begin excavating the pit through mid-1995. In total the development of the West Pit would require stripping topsoil from 313 acres in 1994. At the time Colowyo agreed to this 124 acre permit requirement we believed that as the pit developed activities such as in-pit roads, shot rock, shovel ramps, and other non-regulated in-pit runoff control structures would aid in compliance with the 124 acre requirement. Similarly, subsequent pit developments such as dumps, ramps, reclaimed fill slopes, etc. would ultimately render the 124 acre initial topsoil removal requirement as a useless requirement. Colowyo implemented these concepts during the development of the West Pit to address the 124 acre restriction. First, the decision was made that an in-pit ramp would be constructed to provide for in-pit drainage structure #2 and would serve as a