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7) Colowyo's overall West Pit plan called for increasing the size of structure #2 substantially to a) provide for increased overall hydrologic control, b) provide an access road across the drainage for future truck haulage of rip-rap subdrain material to the West Pit Fill, c) protect the Fill area and shovel box cut areas lower in the drainage and d) potentially remove Y seam coal. As of July 18, 1994 structure #2 was capable of containing in excess of 50 acre-feet of runoff. 8) The Division estimates incorrectly (per the July 18, 1994 letter) that there were 195 acres stripped with drainage flowing directly to the West Pit Pond. The Division's estimate ignores the internal in-pit containment structures providing protection of the hydrologic balance. This misleading estimate does, however, provide the foundation upon which the NOV was written and is clearly incorrect. First, as required by Rule 4.05.6(3)(a) this figure should be reduced by the 38.9 acres of stripping area #3 flowing to control structure #3 and not to the West Pit Pond (structure #1). Secondly, our understanding is that this acreage figure included topsoil stripped areas plus all topsoil stockpiles. Topsoil stockpiles (30.4 acres) were not intended to be included in the acreage calculation with respect to the "124 acre" issue because a) they would not exhibit the same runoff characteristics as topsoil stripped areas, b) half of each stockpile drains away from the stripped areas into adjacent unstripped areas, c) not all stockpiles were completed and some could not drain externally and d) Colowyo's acreage commitment was clearly stated as only "topsoil stripped" areas. The Division's acreage figure for all topsoil stripped areas should more accurately be 164.6 acres (195 acres less 30.4 ~'+a+a~ce topsoil stockpile acres). After being discounted by the 38.9 dre:,~, acres controlled by drainage structure #3, the Division's ~ total acreage estimate in areas #1 and #2 should be 125.70 Cb~ p1a.. acres. The 125.70 acres value does not take into 'F°r¢~~les' consideration any protection of the hydrologic balance obtained from structure #2. 9) As of July 14, 1994, Colowyo's own estimate was 147.28 acres ~. stripped in areas #1 and #2, (81.47 acres stripped in area #1 ~e,,,~ e'n"' and 65.81 acres stripped in area #2) . Colowyo's overall ~ 7,~` summary for the in-place hydrologic control at the time of the "H°ia~~ Division's inspection is summarized by the following table P~~> titled "In-Place West Pit Hydrologic Control, July 14, 1994". The table shows that the combined hydrologic control for stripping areas #1 and #2 provided 14.8 acre-feet of control versus 13.63 acre-feet required for an additional capacity of 1.17 acre-feet.