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near the alluvial wells that collected water pumped from the White River. Additional water enters the cycle from surface moisture on the raw coal and from ground water seepage into the mine. IV.F.1 Water Supply System Three alluvial wells were drilled in the locations shown on Map 90. The wells are approximately 50 feet deep and collect water from an alluvial aquifer fed by the White River. The wells have pitless pump adapters which protrude only 1-2 feet above the surrace of the adjacent ground. The wells were constructed in accordance with standards set forth by the Office of the Colorado State Engineer and the Colorado State Board of Health. The Alluvial Well No. 5 (AW-5) operating plan was modified in February 1990 because of a very poor yield of water from the underground rock formations. Under a revised plan, water from the existing lagoon to the north of the alluvial wells access road (see Map 90) was being pumped into the AW-5 well. The existing well pump then transferred this water to the raw water piping system. Later this plan was abandoned and water is now pumped directly from the surtace lagoon to the raw water piping system. However, the wells are kept standby for emergency use. A dike is constructed to separate Scullion Gulch drainage from the lagoon area. The dike is approximately 100 feet long, 16 feet wide at the crest and 6 feet high with 2:1 slopes. A temporary light access road, 12 feet wide and 860 feet long, was constructed for road base material haulage. Vegetation was cleared as necessary. Topsoil was stockpiled and replaced at the end of the dike construction. Reclamation will follow methods specified in Section V.1.4.h. See Map 90 for the dike and temporary access road location. • During final reclamation, the wells will be removed and the access road base will be scarified and leveled. Topsoil will be spread evenly over the surface and planted with the permanent seed mixture shown in Table V-10. Water from the surface lagoon is pumped into a pipeline which carries it to the water storage tank area. The pipeline corridor is shown on Map 22. The pipeline was constructed of six-inch diameter pipe approved for use in pressurized potable waterlines by the American Water Works Association (AWWA), the Colorado State Board of Health, an applicable plumbing codes and regulations. The pipeline has a maximum capacity of about 500 gpm. The surface portions of the pipeline were buried five to six feet deep to prevent freezing. The pipe was laid in fine soil bedding in a trench approximately three feet wide. Since the area of disturbance was about four feet wide, topsoil was not removed from the pipe trench area. Some clearing of brush and trees and some minor access road construction was required. All earth disturbances including the pipeline trench were reclaimed and seeded with temporary seeding in the spring of 1986. Mine Permit Renewal #3 (Rev. 8/99) IV-26