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La Plata Coal Draft Finings - 3 - May 18, 1987 Conformably overlying the Menefee Formation in the Hesperus area is the upper most member of the Mesaverde Group, the Cliff House Sandstone. The 350 foot thick Cliff House is a grey marine sandstone interbedded with shale. The sandstones are generally lenticular, but may be locally massive, while the shales are generally barren of coal. This unit has been removed by erosion at the mine site. Overlying the Menefee Formation at the mine site is a thin veneer of fine grained materials locally derived from erosion of the Menefee. Recent unconsolidated alluvial/colluvial material forms the surface of Hay Gulch, adjacent to the La Plata No. 1 mine. This material is derived from erosion of the middle to upper Mesaverde Group in the immediate vicinity of the mine site. No landslides or other mass movements have been identified within the La Plata No. 1 Coal permit area. Geochemical sampling of the "A" coal seam and highwall materials indicate that the coal itself has the greatest potential to be an acid-forming material. The presence of this material should not have a deleterious effect upon the local environment provided that no water is discharged from the mine. It is unlikely that significant amounts of water will discharge from the La Plata No. 1 mine, however, the applicant has committed to treating any portal discharge water which has a pH of 6.0 units or less. This plan, when implemented as required, will reduce the possibility of impacting off-site areas. Geochemical sampling of the highwall indicates that these materials are high in iron and magnesium. To assess the impacts of these metals to the post-mining land use, La Plata Coal Corporation has committed to sampling reclamation areas for those parameters if the highwall materials are present within the rooting zone, and to treat these materials as necessary to minimize impacts to reestablished vegetation. This sampling will be accomplished at the time of reclamation in conjunction with the proposed reclamation soil testing plan. The operation is in compliance with the requirements of this section. V. Ground Water Hydrology -Rules 2.04.5, 2.04.7, 2.05.6(3) and 4.05: Ground water hydrology information may be found in the permit application in Section 2.04 and 4.05. Two aquifers have been identified within the area potentially affected by the La Plata No. 1 operation: The Hay Gulch alluvial aquifer; and the Point Lookout Sandstone. Ground water use in the vicinity of the mine is limited. Within a one mile radius of the permit area, one spring and three water wells have been identified.