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operations and reclamation on the hydrologic balance of • underground water should be nil. Although coal seams may carry some water, the amount should be relatively small if other coal mining operations are a guide. Water wells in Sections 22, 27, 33 and 34 should also be unaffected by mining activities. This is because ground waters flowing through the Menefee are diverted into the trough of the perine peak syncline and contribute little to the ground waters along the crest or the southeast limb of the Durango anticline. It is also believed the impact of underground mining operations upon vested water right holders should be nil. 13. Surface Water Information. Three streams pass through the areas held by applicant. The south flowing Animas, the tributary Lightner Creek, and the La Plata River. The Animas and Lightner Creek drain most of the area, and the La Plata River drains the western portion of the area. In addition, surface water flows intermittently down Coal Gulch from snow and occasiona]. precipitation, as well as occasional other surface water flowing across the affected area as a result of snow runoff or precipitation. During the process of excavations, applicant has en- countered water emanating from abandoned underground mining works in the area of the Green Pond noted on Map A-1. The • water in the pond had a pH of about 6 in early spring of 1979, and as of October 1979, had a pH of 5-5.5. Some ferric iron, perhaps colloidal, is present in the water principally from its greenish color. In late 7978 when flow rate from the workings was almost zero, the pH was about 7.5 and some sulphur and iron salts were precipitated around the edges of the pond. When the pond is allowed to fill to its planned depth, oxidation of the underground rocks where the entries are now exposed will decline as the workings become completely submerged several hundred feet north of the old portal. In its final state, the pH of the pond will expectedly be less acidic and remain constant. 47ater captured in the Green Pond tends to have natural purification by settling and aeration. To the extent water overflows from the Green Pond, a second, smaller sedimenta- tion pond has been dug south of the Green Pond to provide for the additional settling of suspended solids and neutralization. The Green Pond and the sedimentation pond are connected by a culvert. Water draining from the Coal Gulch flows in a south- easterly direction toward the affected area, and will be diverted around the disturbed area by means of a conduit. Between the conduit and the disturbed area will be constructed a berm or other barrier to prevent coal fines and other drainage across the affected area from contaminating water in - 8 -