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Colovryo C-1981-019 14 February 2007 Pg 2/ 5 ~d-J Hydrologic Balance: -The operator has stopped the pumping activities in the Section 4 area of the West Pit (where the highwall miner began operating). The water was pumped down enough to access the coal that was stockpiled there and it has been hauled away. There is still a substantial amount of water in the pit and Colowyo is currently planning on leaving it in place and backfilling the pit. -The Section 16 Pond was inaccessible due to snow at the time of the inspection. -The wash bay pond (not a NPDES discharge point) contained water approximately two feet below the top of the embankment and was not discharging. This is a total containment pond and discharge into the Work Area Pond triggers BTEX testing (in addition to regular NPDES testing). The pond embankment was well vegetated and appeared to be stable at the time of the inspection. No erosional problems were noted on the pond embankment at the time of the inspection. -The work area pond (NPDES 002A) contained water approximately one foot below the top of the discharge pipe and was discharging through the weep hole on the discharge pipe. The pond embankment was well vegetated and appeared to be stable at the time of the inspection. No erosional problems were noted on the embankment at the time of the inspection. -The Gossard Pond (NPDES 003A) contained water approximately two feet below the riser pipe and was not discharging at the time of the inspection (although Tony said that the pond did discharge and was sampled in accordance with Colowyo's NPDES permit). The pond embankment was well vegetated and appeared to be stable at the time of the inspection. No erosional problems noted on the embankment at the time of the inspection. The emergency spillway is a 12" culvert. -All of the roadside ditches appeared to be clean and functioning as designed at the time of the inspections. No erosional problems, sediment build-up or blow-outs were noted at the time of the inspection. -The West Pit Pond (NPDES 008A) contained water to the bottom of the gated valve on the discharge pipe and was not discharging at the time of the inspection. There was also a small pool of water in the presettling sump at the inlet of the pond. The pond embankment was well vegetated and appeared to be stable at the time of the inspection. No erosional problems noted on the embankment at the time of the inspection. The emergency spillway is an open, trapezoidal riprapped channel. The spillway was stable and well maintained at the time of the inspection. -The East Taylor Pond (NPDES Ol OA) contained water approximately one foot below the weep hole (approximately eight feet below the top of the discharge pipe) and was not discharging at the time of the inspection. The pond embankment was well vegetated and appeared to be stable at the time of the inspection. No erosional problems noted on the embankment at the time of the inspection. The emergency spillway is an open, trapezoidal riprapped channel. The spillway was stable and well maintained at the time of the inspection. The water that was pumped from the Section 4 area of the West Pit into the riprapped spillway of the East Taylor Pond did not cause and erosional or stability problems. The diffuser appears to have worked very well. Now that pumping has ceased and all of the equipment has been moved from the site, the operator needs to remove the flex-tubing and diffuser from the pond embankment.