2017-04-28_REPORT - C1981038 (4)

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Surface Water Monitoring Stations: SMALL AREA EXEMPTIONS The west side of the east mine fan level is defined as a small area exemption since drainage from this area is not conveyed to a sediment pond. One sample point is defined at this location and sampled for conformance with the NPDES discharge alternative limitations requirements associated with discharges occurring because of precipitation events of less than the 10 -year and 24-hour magnitude. In these instances, settable solids and pH limitation must be met. No samples were collected during 2016 from this SAE point. Coal Member of Mesaverde: All previously monitored drill holes have now collapsed and are no longer monitored. The removal of these monitoring points is explained in TR -34. Surface Water Monitoring Stations: PONDS East Roatcap Creek- Eleven ponds in the East Roatcap Creek drainage were monitored during the year (refer to Table 1 and Map No. 4-1). Ponds were monitored quarterly for water levels and field parameters if they were discharging. No evidence of mine impacts was noted. During 1994 retreat mining was done under Ponds 10-1, 10-2, 10-3, 10-4 and 10-11. Advance mining occurred under pond 88 during 1997. The East Roatcap Creek Ponds were physically intact throughout the year and showed no subsidence effects. Ponds 1001, 1002, 1003, 1004, 1007, 1009, 1014, 1501, 8700, 8800 and 8900 were permanently suspended with the approval of TR -61 and will no longer be part of the monitoring program. Stevens Gulch - Two ponds were monitored within the Stevens Gulch drainage (refer to Table 5 and Map No. 4-1). Ponds 85 and 13-7 were monitored quarterly for water levels and field parameters. Pond 85 was undermined by Panel B in 1992. Pond 13-7 was also undermined during 1992. No subsidence impacts or other irregularities were evident at either of these locations during the year. Ponds 1307 and 8500 were permanently suspended with the approval of TR -61 and will no longer be part of the monitoring program. CDPS Monitoring Points DMRs are submitted quarterly to the Colorado Department of Public Health and Environment with copies to the Division of Reclamation, Mining and Safety and are included herein by reference. Conclusion Hydrologic monitoring was extended into the northern portion of the East Roatcap Creek drainage during 1993 to fit newly acquired lease areas and revised mine plans. Mining operations were suspended during December 1997 and have not resumed. Hydrologic monitoring conducted during 2016 did not show mine related impacts to the local hydrology were occurring. Water quality remains good overall and no physical impacts have been noted at any of the monitored locations that would suggest adverse effects associated with the historical mining operations of the Bowie No. 1 Mine. 4