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~J- • south and west parameters na0 Jeen Snape7, ConStrUCtiOn Of the main subsurface Grain s'rstem .vas oeeun. iieng most of the alignment, the Grain trench was excava*_ea scout 5 feet oelow the ground surface and at least one foot into bedrock. Tong much or the alignment, the drain .vas excavates almost =_ntirely into oedrocx. Photograpn b Shows Some or the trencn excavation. The deoth to bedrock increased to more than 12 feet at the north end of the west drain line. .about the northern 200 feet of the line 'was oottomec in ;tiff clay, at least ~ feet beiow the groune surface. 'de do not oeiieve that this variance from plan along the northern 200 feet of the drain line •viil adversely affect staoility of the waste bank. ,any leaching wnicn 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 1~ON filter fabric and a o-inch diameter perforated PVC pipe placed as shown on Photograph 6. The trench was filled ~,vith free draining gravel and the filter fabric loped across the top of the gravel as Shown on Photograpn 7. At least 8 inches of gravel was then placed aver the lapped filter cloth for protection from vehicle traffic. Photograph 3 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. Photograph 11 shows an overall view of the disposal area. As of our site visit made April 22, 1982, topsail and organic matter had been removed from the coal processing waste bank area. The 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 constructed 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 or the channel appeared to be flatter than 1 percent. The placement of riprap, 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 accomplishes on the surface diversion ditches.