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-3- south and west parameters had been shaped, construction of the main subsurface drain system was begun. Along roost of the alignment, the drain trench was excavated about 5 feet below the ground surface and at least one foot into bedrock. Along much of the alignment, the drain was excavated almost entirely into bedrock. Photograph 5 shows some of the trench excavation. The depth to bedrock increased to more than 12 feet at tl~e north end of tfie west drain line. About the northern 200 feet of the line was bottomed in stiff clay, at least 5 feet below the ground surface. We do not believe that this variance from plan along the northern 200 feet of the drain line will adversely affect stability of the waste bank. Any leaching which is developed through the pile should flow over the relatively impermeable clays and be collected in the drain. After excavation of the drain trench, the trench was lined with Mirafi 140N filter fabric and a 6-inch diameter perforated PVC pipe placed as shown on Photograph 6. The trench was filled with free draining gravel and the filter fabric Taped across the top of the gravel as shown on Photograph 7. At least 8 inches of gravel was then placed over the lapped filter cloth far protection from vehicle traffic. Photograph 8 shown a completed section of the subsurface drain. Figure 1 presents the results of a gradation analyses which was conducted on a sample of the drainage gravel. The results of the analyses indicates that the material used meets the specifications shown on the construction plans. There was an existing coal processing waste stockpile in the southern portion of the site. Photograph 9 shows a portion of the pile. The stock- pile was spread across the southern one-half of the waste bank area after the area had been shaped and compacted. The area below the stockpile was then compacted. Photograph 10 shows a portion of the waste bank area after the previous processing waste had been spread. Photograpi~ 11 shows an overall view of the disposal area. As of our site visit made April 22, 1982, topsoil and organic matter had been removed from the coal processing waste bank area. Tlie subsurface drain had been installed in 'general conformance with our recommendations. The ground surface across most of the site had been shaped to drain towards -, the toe drain. It,aPpears that major low areas which would have tended to • collect water had been filled. Surface diversion ditches had been constructed as of our visit made May 6, 1982. In general, the ditches_appeared to have been consl:ructed in general conformance with the design cross-section. There were some isolated areas where the ditch did not appear to be at least 3 feet deep and the grade of the channel appeared to be flatter than 1 percent. The placement of rip rap, where required, had yet to be completed and the channel had not been seeded. Mr. Rick Mills of Empire Energy and Mr. Jerry Jones of Palisade Construction were informed of the work to be accomplished on the surface diversion ditches.