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the 14.2i~ acres of disturbed land if that, in fact, was the case. The final total of 4.2 acre-feet is the min- imum required sediment storage volume. Show data and calculations used to compute the magnitude of a 10-year, 24-pour storm. Provide supporting evidence that no out- flow will occur as a result of a 10-year, 24-hour storm. Provide plans and specifics for ttie dewatering device, conduit or spillway. See 784.16 (a)(1)(v) with reference to short-circuiting. Show data and calculations for com- puting the runoff from a 25-year, 24-hour precipitation event. Provide data oii emergency spillway grades and vel- ocities. Show a dam cross section which indicates place- ment of principal and emergency spillways and height of settled dam with reference to water surface with emergency spillway flowing at design depth. Indicate final con- structed height of dant. Provide calculations for des- igning the minimum top width of the dam. Provide calcul- ations for designing the combined upstream and downstream side slopes of the settled dam. Include in the design plan, provisions for dam foundation area preparation, fill material to be used, and placement of fill. Since pond storsge volume exceeds 20 acre-feeC, comply with the per- _ - -~ formance standards found in 817.4u (q). Describe pro- visions for stabilization of the dam and surrounding areas. 784.19 EA No. O1L and the application submitted to the Colorado Mined Land Reclamation Board mentions the burial oi' tox- ic or acid producing materials at a minimum depth of 15 feet below reclaimed subsoil. The main body of the ap- plication states however, that all waste will be returned to underground workings. The mine plan map does not indi- cate an area set aside for surface burial of underground waste. If such surface burial is contemplated, methods and sites must be identified and described in accordance with 817.71 - 317.74. Each plan should be prepared pur- suant to 780.35. 744.20 Provide a statement, positive or negative, as to the po- tential for subsidence damage to existing structures or renewable resource lands. Estimates of a maximum subsi- dence of two inches over some areas of the mine and of possible damage to the ephemeral stream traversing the mined area should be fortified with data and calculations. If subsidence damage is possible as determined by the ap- plicant or the regulatory authority, a subsidence control plan should be formulated pursuant to the requirements of this section. lU