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The operator's plan for non-coal processing waste disposal on site is <br />in compliance with the regulations. Non-coal processing waste such as <br />paper trash, garbage, scrap metal, and other non-hazardous waste is <br />currently disposed of at the Oelta County Landfill. <br />X. Backfilling and Grading <br />COVCC's application for a permit for the Orchard Valley Mine proposes <br />a reclaimed final configuration for the surface facilities areas of <br />the mine which consists of a partial backfilling scheme. In the <br />preliminary adequacy review of the original permit application, the <br />Division stated that it considered their proposal to be inadequately <br />supported within the application. Further, the Division required the <br />applicant to complete an appropriate geotechnical and stability <br />analysis to demonstrate that the proposed final configuration would be <br />stable and would satisfy the requirements of Rule 4.14 and 4.27, <br />"Operations on Steep Slopes." The results of the analyses would then <br />be utilized by the applicant to prepare a detailed engineering design <br />which conforms with the above-enumerated regulations. <br />The operator retained the services of Merrick and Company and <br />Geo-Hydro Consultants, Inc. to investigate the slope stability of the <br />entire surface facilities area at the Orchard Valley Mine. Phase I of <br />this study was completed and a summary report, prepared by Geo-Hydro <br />Consultants, Inc., was submitted to the Division for review on <br />July 21, 1981 (See Volume 6>. The analysis, prepared in accordance <br />with the present state-of-the-art of geotechnical analysis, determined <br />that no immediate major hazards existed at the mine site. The report <br />does observe, however, that some local stability problems .exist and <br />the factors of safety of individual cuts and fills will have to be <br />increased by redesign and reconstruction to achieve a stable final <br />reclaimed configuration, in accordance with the regulations. <br />Geo-Hydro, Consultants, Inc. completed the Phase II analyses on <br />April 15, 1982, 1n accordance with the stipulated requirements of the <br />originally approved Permit (See Volume 6). The stipulated tasks of <br />the. Phase II analyses included evaluation of nearby landslides mapped <br />by the Colorado Geological Survey, completion of test drilling and <br />test pits, installation of monitor wells, soil and rock testing, and <br />the completion of a series of stability analyses far current slope <br />configurations of the existing surface.facility area at the Orchard <br />Valley Mine. <br />The operator, in conformance with recommendations made by its <br />geotechnical consultants, has installed sophisticated tilt-metering <br />devices within several of the fill benches which exist within the <br />surface facilities at the Orchard Valley Mine. The purpose of these <br />devices is to collect additional geotechnical data with which to <br />verify past analytical assumptions and with which to complete fins l <br />analysis and design, originally stipulated as Phase III of the surface <br />facility studies, within the approved original permit. <br />Utilizing the results of Geo-Hydro, Consultants, Inc .'s analyses, <br />Merrick & Company, Inc., design consultant to the operator, completed <br />-34- <br />