2011-04-08_INSPECTION - C1981008

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March 29, 2011 C- 1981- 008/New Horizon Mine MLT • The water level in Pond 007 was too low for discharge to occur. • Pond 008 was not discharging, Mr. Gubka said that the CCC Ditch had been turned on for an early run to fill stock ponds in the area. The landowner for Pond 008 (Burbridge) had asked WFC if the pond cold be filled further during the pond run. The answer is no - the pond must still have available capacity sufficient to hold the design precipitation event, as approved in the permit. • Pond 009 was dry, but Pond 011 was discharging. The vegetative cover on the inslopes of Pond 011 continues to improve from year to year. Mr. Gubka showed us the continuous flow recorder attached to the Parshall flume at the pond outlet (Photo 5). • Ponds 012 and 013 were dry, with the exception of groundwater -fed puddles in the pond bottoms. • The operator is awaiting final approval from CDPHE WQCD to divert water pumped from the pit to Pond 013, rather than Pond 011. Once the change is made, Pond 013 is likely to discharge continually, while Pond 011 will no longer do so. Pond 011 discharges to Enstrom Draw, which flows into Tuttle Draw. Pond 013 will discharge directly into Tuttle Draw (Photo 6). • The operator was in the process of constructing Pond 015 and the associated collection ditch. Pond 015 was approved under PR -06, and fits snugly into the southern corner of the western boundary of the WFC parcel. It has been designed to hold the 100 -year 24 -hour storm, without discharging. Excavation of the pond was accomplished into solid bedrock (Photo 7). The location of the collection ditch had been marked eastward along the northern slope of Enstrom Draw using a series of orange - painted rocks (Photo 8). Mr. Gubka said the ditch has been designed at a gradient of 0.5 %. Where the collection ditch crosses a series of small, natural drainages, the ditch will be constructed in fill material. The natural drainages, which drain undisturbed areas, will be directed through small - diameter corrugated metal pipes (CMPs) beneath the collection ditch fill sections. • We visited the CCC Ditch concrete diversion box located outside the northeastern boundary of the permit area. Mr. Gubka explained the system of charging the 26" and 12" buried pipelines (Photo 9), and construction and maintenance of the box in order to prevent the access of debris into the pipeline and irrigation systems. GENERAL MINE PLAN COMPLANCE: • The mine's shovel was not in operation at the time of the inspection. WFC has purchased a new drill rig; the rig was stationed on top of the exposed Bench 2 Overburden surface. • Inside the pit, below Ramp 2, we observed a front -end loader at work exposing the top surface of the Lower Dakota coal seam. Interburden between the upper and lower seams had been fractured prior to the work. Mr. Gubka explained that the loader will typically mix the coal from the two seams at a ratio of 4 parts lower to 1 part upper (which has a higher sulfur content) prior to loading the coal into trucks for hauling to the Nucla Generating Station. • Periodically, coal is temporarily stored in a stockpile (the size of which is limited by the mine's Emissions Permit) located in the backfilled area behind the pit (Photo 10). This is typically due to the coal's being wet, and needing time to drain, before being transported to the plant. Number of Partial Inspection this Fiscal Year: 6 Number of Complete Inspections this Fiscal Year: 3 Page 4 of 16