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stratigraphically lower aquifers whose recharge areas do not include Pine Gulch. The • Pine Gulch area is also not one utilized for agricultural or silviculturalproduction of food and fiber nor does it serve as a pasture land. The confluence of Pine Gulch and Hay Gulch approximately three miles downstream from the mine was determined to be an alluvial valley floor on which agricultural activities are conducted. These activities however, do not rely on the surface or ground water resources originating in the Pine Gulch area. Provisions of the proposed mining plan, furthermore, will minimize any potential for mining related subsidence impac[s on the Pine Gulch drainage. Elongated pillars will not be extracted during final retreat. As a result, [he Pine Gulch drainage area will be assured of continued long term stability. XIV. Operations on Alluvial Valley Floors A. The Division has determined that an alluvial valley floor exists within the affected or adjacent area. Therefore, the following findings are in order for the alluvial valley floor known as Hay Gulch located 7 mi]es SW of Hesperus, Colorado. There are cuaently three coal mining operations located within Hay Gulch: the King Coal Mine (permitted, active), the Blue Flame Coal Mine (revoked and reclaimed), and the Ia Plata No. 1 Mine (revoked and reclaimed). All three mines are considered in the alluvial valley floor discussion. • Field observations by Division staff and information contained in permit applications indicate that small areas of unconsolidated stream-laid materials are present in adjacent drainages. However, these areas are not extensive enough to meet the size criteria of AVFs. It has been determined that Hay Gulch meets the criteria for an AVF based upon three findings: (1) The valley contains unconsolidated stream-laid deposits; (2) The valley contains sufficient water to support agricultural activities as evidenced by (a) the historical use of flood irrigation in the area, and (b) the demonstrated capability of the area to be flood irrigated, and (3) The valley has demonstrated subirrigation. It should be noted that Hay Gulch does not presently contain a stream. It is thought that this is due to agriculmral practices in the gulch which divert naturallyoccurring flow into the Hay Gulch Irrigation Ditch. Furthermore, it is thought that the original channel has been removed by local agricultural activities. The Hay Gulch Irrigation Ditch, which parallels La Plata County road 120, is used for flood irrigation purposes in the vicinity of present mining activity. Ic has been demonstrated that the naturally occurring water table of the AVF varies from above ground surface to about three feet below the surface. This demonstrated that sufficient water is available for subirrigation purposes. Furthermore, the identified . land use on the AVF is primarily pastureland with occasional hay production. The essential hydrologic functions that supply water to the AVF are both flood irrigation 22