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As noted above, the existing surface disturbance resulting from surface facilities equals 9.2 acres; .84 acres of access/haul road and 8.36 acres of bench/portal facilities. No further disturbance is proposed. To control runoff from this disturbed area, the applicant has constructed a comprehensive drainage control system consisting of two sedimentation ponds, a series of interconnected buried culverts and an interceptor ditch. Flow from the disturbed area is routed via the culvert/ditch system into the sedimentation ponds. The ponds are designed to contain at least the 10-year, 24-hour storm event; one pond, located at the northwestern edge of the disturbed area, with a 1.5 acre-foot capacity, will hold the flow of a 25-year, 24-hour event without discharge. No discharge has historically been recorded from this system. Division inspection reports indicate the pond remains dry most of the year. This surface water and sediment control system are in compliance and will prevent degradation of surface water quality. Information concerning drainage control structures can be found in Section 2.05.6 and Maps C-4 and C-9 contained in the permit application. The second area of potential impact on water quality may result from the surface manifestation of subsidence. Disruption of the surface could lead to a tear porary increase of suspended solids in runoff from the permit area. Such an impact is not considered significant. This is due primarily to observations from over 40 years of underground mining at the site. These observations indicate little, if any, surface disruption due to past underground mining. Of greater concern is the potential disruption of the small irrigation ditch bisecting the permit area from northeast to southwest roughly along the drainage divide between Pine and Hay Gulch. Here, subsidence would result in a disruption of this supply of surface water. Once again, however, observation from over 40 years of mining in this area do not indicate that any disruption of this water supply have occurred. The mine workings, where the effects of rupturing the ditch would be seen, remain dry. To ensure the continued operation of this ditch, the applicant has submitted an agreement from the landowner allowing access to repair any damage and committed to quay rterlU monitoring of the ditch. The operation was found to be in compliance with the subsidence control and monitoring program under XXIII of this findings document. The proposed operation is in compliance. VII. Water Rights and Replacement (2.04.7(3), 2.05.6(3)(a)(ii), 2.07.6(2)(c), 4.05.15) As discussed in V, Ground water Hydrology, proposed operations at the King Coal mine are not expected to impact existing water rights to ground water sources. Impoundment of water in sediment control structures will not exceed the allowable 2 acre-feet per sediment pond limit established by the Colorado Division of Water Resources. Therefore, no impacts to existing water rights to surface water sources is expected. Since no impacts to existing water rights is antici- pated, no replacement plan is required. The proposed operation is in compliance.