2012-04-23_INSPECTION - C1981012

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Apri123, 2012 C- 1981- 012/New Elk Mine JHB EXCESS SPOIL and DEVELOPMENT WASTE — Rule 4.09 Placement; Drainage Control; Surface Stabilization: NECC continues to work the DWDA adjacent to the Purgatoire River. The pile appears taller than 30 ft. high, but there was no evidence of slumping of the sides of the pile, and NECC is maintaining an 8 -12 ft wide corridor between the south toe of the DWDA and Ditch D13. A berm and the Stream Buffer Zone exist between Ditch 13 and the Purgatoire River. There was no sign along the length of the DWDA that any development waste material had been spilled over the berm and entered the river. The inspector collected slope length and angle information from the south side of the DWDA in order to calculate the current height of the pile. An excavator was actively working the top of the pile to slope the sides of the pile to the approved grade. NECC is currently permitting a small footprint enlargement of the DWDA to the NW with the Division, MR112. As of 4/24, MR112 had not been approved based upon remote access to the Division's laserfiche system from the mine site. 3 measurements were collected along the south side of the pile. The first was approximately 80 ft. from the eastern toe of the DWDA. Angle of the pile was 33.5 degrees at the toe of the pile looking towards the top of the pile using a Suunto inclinometer. The slope length (hypotenuse) of the pile was 60 ft. (20 yds.) using a Bushnell yardage -pro rangefinder. Based on these measurements, the height of the DWDA at this location is approximately 33 feet. The second measurement was taken even with the footbridge over the Purgatoire River. The slope angle from the toe of the pile to the top of the pile was 33.5 degrees, the slope length was 75 feet (25 yds.). Based on these measurements, the height of the DWDA at this location is approximately 41 feet. The third measurement was collected 60 foot west of the footbridge (even with the pump in the River). The slope was convex at this point so the inspector stepped 11 feet to the south of the toe of the pile to collect the values. The slope angle from 11 ft. south of the toe of the pile to the crest of the pile was 25 degrees. The distance from the data collection point to the crest of the pile was 60 feet (20 yds.). Based on these measurements, the height of the DWDA at this location is approximately 25 feet. The DWDA is designed not to exceed 30 feet in height. and no greater than 21:1h slopes. NECC needs to continue to bring the DWDA into conformance and assure that compaction requirements are met. NECC has also submitted a technical revision with the Division to construct a new DWDA at the reclaimed west portal area. This area proposed for the West DWDA was inspected and walked. Most of this area has previously been disturbed by prior mining activities. Much of the area has been reclaimed with a portion of the area being maintained for west portal area access and west portal ventilation. 4 truck dumped piles of development waste were placed west of the RDA conveyor in the area topsoil pile 92 had been. Upon noting these piles, NECC removed them from this location and placed them on the DWDA. Shawn stated these piles had been temporarily placed here during snow removal operation the preceding week and needed Number of Partial Inspection this Fiscal Year: 9 Number of Complete Inspections this Fiscal Year: 3 Page 3 of 16