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9 VIII. Alluvial Valley Floors - Rules 2.06.8 and 4.24 The Division presently cannot make the required findings concerning alluvial valley floors (AVF). The following information must be submitted before the Division can propose a decision to approve the Coal Ridge No. 1 permit application. Requirement No. 3 1) The applicant states that "the downgradient wells, OW-8 and OW-4L, should detect any degradation of water quality due to the coal processing operation." The Division agrees with this portion of the proposed monitoring plan for monitoring the AVF below the surface facilities, but there is no mention of a plan to monitor the effects of the coal refuse embankment on the AVF downgradient from that structure. A plan for monitoring any surface water and ground water quality effects must be submitted. This plan must include collection of one year of baseline information if applicable. 2) The applicants discussion of the significance of the AVF area proposed to be disturbed only discusses the acreage to be disturbed. In order for the Division to make a finding concerning significance of the proposed area to be disturbed, the applicant must provide an economic demonstration showing that the 6.4 acres to be disturbed are an insignificant part of the AVF farming unit. 3) The applicant must submit a quantitative assessment of the effects of the coal refuse embankment on the quantity and quality of surface and ground water supplying the AVF downgradient from the pile. No assessment is contained in the application. 4) The applicant must provide a description of the methods that will be used to restore the essential hydrologic functions of the AVF at the slot storage area. Since it appears that the essential hydrologic functions of this portion of the AVF are those which make the area flood irrigable, the applicant must submit a plan for restoration of the soil profile and ditch system in this area. 5) The applicant states that approximately 600 acre-feet will be used consumptively by the mining operation each year. This water is planned to be taken from the Vulcan Ditch which is used to irrigate the AVF in the facilities area. Furthermore, it is stated in the application that the apparent irrigation application rate is 10 to 12 acre-feet per acre per year. As presently stated, the Division cannot find that the proposed operation will not affect the quantity of water supplying the AVF since as much as 50 percent of the water supply will be removed. However, it is apparent that 10 to 12 acre-feet per acre is an excessive rate of application. The applicant must submit an estimate of the amount of water actually required to be applied to the irrigated portion of the AUF in order to maintain production levels. The application must then commit to supplying that amount of water at all times except when the Vulcan Ditch is flowing at an amount greater than is required. This means that irrigation of the AVF must take precedence over the mining operation needs.