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<br />6 <br />Certified engineer's reports of the backfilling, grading and compaction for both portal areas <br />have been received by the Division. <br />The Division took slope measurements on the backfilled and regraded slopes during the <br />March 8, 1995 bond release inspection using Abney levels and measuring staffs. The Portal <br />No. 2 (Helen Portals) highwalls and face ups had been backfilled using refuse as per the <br />design plans in section 2.05.3(8) of the permit. Thirteen slope measurements were taken <br />along this backfilled portion and the West-facing slope of the coal waste bank, with a <br />resulting average slope of 16.0° or 28.7% (standard deviation of 2.0). This is a gentler slope <br />than the approved maximum of 3h:ly (33%). These highwalls extended approximately 1300 <br />feet and were roughly 50 feet high prior to backfilling. <br />The South-facing slope of the reclaimed coal waste bank directly north of the refuse <br />collection ditch No. 1 was the subject of six slope measurements with an average of 17.4° <br />or 31% (standard deviation of 1.5). The length of this South-facing slope is approximately <br />700 feet (measured along its toe) and is the southern extent of the originally approved coal <br />waste bank. This is gentler than the required 33%. One location adjacent to the lower <br />catchment basin/check dam structure exceeded the 33% gradient by 4%. <br />Rule 4.10.4(5) requires a minimum of four feet of non-toxic cover for reclamation of an <br />approved coal mine waste bank. Permit Section 2.05.4(2)(c) commits the operator to <br />constructing the coal waste bank with this minimum four feet cover. During the March 8, <br />1995 inspection, the operator dug twelve test pits with a hydraulic excavator for the <br />Division's verification of cover depth over the coal refuse material. The average cover <br />depth was 4.72 feet, which exceeded the cover depth requirement. <br />The No. 1 Portals (Animas) were backfilled with overburden material recovered from <br />approved "borrow' areas throughout the mine yard area. Stability analysis was projected by <br />Energy Fuels in section 2.05.4(2)(c) of the permit. Nine slope measurements were taken <br />on the north facing slopes at the location of the No. 1 (Animas) Portals. The backfilled <br />highwall extends approximately 450 feet, with an additional 200 foot extent of the backfilled <br />slope consisting of the regraded substation area. The height of the highwall prior to <br />backfilling was approximately 20 feet high. <br />These measurements demonstrated an average slope of 15.4° or 27.6%. The overall slope <br />is gentler than the 3h:ly (33%) required in the permit, and meets the regulatory criteria. <br />A short segment of the regraded slope at the southern extent of the regraded substation <br />area has a gradient of 25°, which corresponds to a 2h:ly slope. The length along the toe of <br />this steep section is approximately 200 feet. <br />Energy Fuels also backfilled and regraded a 400 foot section of a 25-foot high highwall <br />located between the shop building and the concrete pads (the former prep plant). This area <br />was disturbed prior to the enactment of the Colorado Surface Coal Mining and Reclamation <br />Act and was not reaffected after its passage until reclamation. The Division collected four <br />