2016-07-15_GENERAL DOCUMENTS - M1988044

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B. Material used in backfilling- Backfilling at the current mining pit primarily used overburden plus some wash fines from the processing plant. C. Maximum, minimum, and average slopes- Finished slopes in all the backfilled areas in the pit are far from completion and therefore any statement of slope gradients in these areas would be premature. D. Deviation from original elevation for new backfilled land-Those deviations have only approximately been taken into account,but as the filling continues and a more finished condition is approached elevation deviations will need to be considered more. 3. Processing facilities- Nothing has changed here. 4. Access corridors- No change in access corridors. 5. New soil and overburden stockpiles-No significant amount of soil was stockpiled because the pit area did not expand in the last year. RECLAMATION ACTIVITY IN THE LAST YEAR: 1. Climatic summary of previous year- The following graphs on separate pages show the climatic patterns from January 1, 2015 through the first half of 2016. These data are for the official weather stations for Denver(Denver International Airport) and Centennial (Englewood). As has been previously determined, the Coal Creek site, on average tends to be somewhat cooler and wetter than DIA, but the overall pattern at DIA is largely applicable to the specific Coal Creek area. The official record for the Centennial Station is also used as it is closer to Coal Creek and provides some comparison with Denver. The Centennial station is comparatively new and so the period of the record for that location is fairly short. From 2012 to 2015 the record is complete and comparable with Denver data, although the long term medians are not reliable for Centennial due to the short period of the record. Past examinations showed that the stations surrounding Coal Creek(Bennett,Parker, and Cherry Creek Dam)were about 5 to 10 percent wetter and a couple of degrees cooler, on average, than DIA. However, consistency in the differences is often lacking on the annual scale with the three nearby stations showing more variation between themselves than the average of the three stations vary from DIA. Also, because recent records from those stations are often not continuous the data set itself for each station shows high variance. In 2015 between July 1 and December 31 precipitation was well above normal during the entire period for both Denver and Centennial. But in the first half of 2016 precipitation fell back to near normal for Denver and very slightly below normal for Centennial. Keep in mind that the statistical norms for the two stations are based on a very different length of record. Comparing the actual amounts received shows that both were nominally similar for a six month period. For such a short period, a one inch difference in precipitation is probably not climatically significant. Status report for 2016 due July 15, 2016 Page 3 of 6