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3) Clean-up of coal fines deposited in [he proximate portion of Foidel Creek. Environmental Staff constructed a high pressure hose system with a 300 gallon tank. A small vacuum tanker track was hired to remove coal fine material and dispose of it in a section of the refuse pile. The Pond E dischazge channel was cleaned using the high pressure water system. Coal fines were washed off the banks of Foidel Creek and eventually driven into small basin aeeas, where the vacuum truck and TCC Environmental personnel could remove the fines. Clogged culverts were cleaned using the vacuum hose in conjunction with the high pressure water system. Final cleanup was completed by mid-October 2006. For additional detail, please refer to abatement communications for NOV CV-2006-006 Constmction DewaterinQ Permit CO-G072272 In July 2006, Twentymile Coal contacted Mr. Chris Gates of CDPHE regarding this site and later submitted a Constmction Dewatering -Wastewater Dischazge Application, which was subsequently approved (Outfa11001A under CO-G072272). Mr. Gales also requested preliminary analyses of [his water for alkalinity, COD, pH and TDS. A sample was collected and analyzed for these parameters. A dischazge channel was constructed in late July, and weekly monitoring of discharge from outfall OOIA began in August. Note that water was pumped from the sedimentation pond through OOIA on an as needed/ sporadic basis. Pump flows were estimated. CDPHE Discharge Monitoring Reports were copied to DRMS. In summary, Outfall OOlA was recorded as flowing in July and for two weeks in August 2006. There was no further flow in 2006. Two exceedances (30 day average and 7 day max) were obtained for total suspended solids (TSS). The first sample in the month exhibited a value of 14 mg/1, while the second exhibited a value of 94 mg/I. This may have resulted from the pump system agitating the water from the sedimentation pond during low water. The system was examined and adjusted accordingly. Note that the site dischazged for a few days in the spring of 2007. No exceedances were noted, and there has been no further discharge to date. 3.8 2006 Inflow Survey The annual inflow survey was performed during November. During the 2006 inflow study, flow rates and field parameters were recorded for measurable inflows from the accessible areas of the underground mine. Results of the 2006 survey are presented on Figure 117, 2006 Inflow Study Mined Area (in map pouch a[ back of report). The WMD was closed in 1996 at that time inflows were 52 gpm. Note that water elevations for the WMD were monitored periodically at the Fish Creek Borehole. Our best estimate is that inflows for the WMD aze still on the order of 50 gpm. Longwall mining was completed in the EMD by early-January 2001. Production from the NMD, 12 Rt Longwall Panel, was underway by late January 2001. The EMD was permanently sealed in October 2001 removing all access to the 6 Rt and 7 Rt gate roads. Thus, no measurements are available in this azea for 2006. Historical data is available in previous AI-IRs. The last flows measured for 2000 showed seasonal variations, with an average annual flow of approximately 65 gpm. The EMD was monitored periodically at the lORT well shaft during 2006. Norther Mining District (NMD): At the time of the 2006 inflow study, the mine operation was nearing the end of the 19 Rt panel. During 2006, the main sources of water came from the two most recent shafts in the 6MN area, and two fault crossings. Total inflow is estimated to be on [he order of 90 gpm. Inflows continued in the Northeast Submains, although there appeats to be a continued decrease in ceiling dripping. The highest inflows 14