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licensed pickup service for refinery recycling. See Tab 9, page 14-28 and 14-29 of the permit
<br />application document.
<br />VI. Coal Mine Waste and Non-Coal Processing Waste
<br />Information on coal processing waste and coal processing waste embankments can be found in Section
<br />2.05.3(8), Tab 13, of Volume 3 of the application.
<br />Three permitted refuse piles, CRDA-I, CRDA-2, and RSRDA, will be constructed to the
<br />specifications outlined in Tab 13 text, and in Appendices 13-4, 13,E and 13-6 of the permit. See
<br />Exhibits 4, 5, 9A, 9B, 18, 51, 52, 53 and 55, for further information. Reclamation of the refuse
<br />disposal areas is addressed in various sections of Tab 14, Volume ~, of the permit application, and
<br />reclamation specifications are depicted on Exhibits 6C, 9C, 26, and 18.
<br />Raw coal mined at the Roadside Mines is processed at the preparation plan[, located within the
<br />Roadside South facilities area, and clean coal is conveyed to a unit train loadout facility on the
<br />opposite side of the river, approximately a mile to the north. The reject material is transported by
<br />truck to the disposal sites in Coal Canyon. CRDA-I and CRDA-2 are currently (January, 2000)
<br />active. Ao additional refuse disposal area in Coal Canyon (CRDA-3), along with an associated
<br />permanent stream diversion, soil stockpiles and drainage control structures, had been
<br />conditionally approved, but was withdrawn from the permit in January, 2000.
<br />Refuse disposal within the Roadside Refuse Disposal Area (RSRDA) was completed in the early
<br />1980's, and the slopes of the pile were temporarily stabilized. The Flat top of the RSRDA is a
<br />permitted supply storage area, and final reclamation of the RSRDA will occur in conjunction with
<br />reclamation of the entire Roadside South facilities area. A stability analysis for [he RSRDA is
<br />provided in Appendix 13-4. Final grading is discussed in Tab ]4.
<br />The lower three benches of CRDA-I and CRDA-2 were covered with the approved thickness of non-
<br />toxic cover, seeded, and mulched in the late summer/fall of 1994. The Cameo Refuse Disposal Areas
<br />will be reclaimed contemporaneously, as described in Section 2.05.4(2)(a), Tab 14, Vo1.5.
<br />Geotechnical analyses for CRDA-I, and CRDA-2, are provided in Appendices 13~ and 13-~ of the
<br />application. CRDA-I has been constructed with three rack underdrains, and construction
<br />specifications include 2:1 slopes with 10' wide benches on 30' vertical intervals. The benches are
<br />sloped to the inside and graded to drain to perimeter ditches along the sides of the pile. CRDA-2
<br />specifications are similar, with the exception that pile design does not incorporate underdrains, and
<br />slope between benches is not to exceed 2.5:1.
<br />Stability concerns associated with higher than anticipated water levels in Piezometer CRDA-01
<br />resulted in suspension of waste disposal at the site in 1988, pending drainage modifications and
<br />stability re-evaluation. Between 1988 and 1993, the lower three benches were regraded to provide
<br />for better slope stability and drainage. Surface drainage was improved by the construction of diversion
<br />ditches that allow surface runoff to exit azound the pile instead of contacting the face.
<br />A stability evaluation was performed in the spring of 1994 by Western Engineers, Inc. As a part of
<br />the study, pump testing was conducted in existing piezometers and 30 additional piezometers were
<br />installed to evaluate phreatic surfaces and pore pressures. The results of the study showed the pile to
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