_INSPECTION - C1981019 (42) - Laserfiche WebLink

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Colowyo C-1981-019 27 April 2009 Pg 3/4 Hydrologic Balance (cont.): - The Streeter Pond (NPDES 001 A) contained water approximately 1-1/2 feet below the top of the discharge pipe and was discharging from the weep hole on the pipe. The discharge measured 0.1 on the flume and was clear. There was a very small amount of water flowing into the pond from the spring runoff but the inlet of the pond remained free of sediment (the pond was cleaned in February 2009). The pond embankment was stable and well vegetated and no erosional problems were noted. The large culvert that carries water from Goodspring Creek under Colorado Highway 13 was clear at the time of the inspection (although this culvert is the responsibility of CDOT it does get clogged up and cause water to back-up for quite a distance). - The Section 28 Pond (NPDES 012A) contained a small amount of water but was not discharging at the time of the inspection. There was a small amount of sediment at the inlet of the pond from the runoff but this is not a problem at this time. The vegetation on the embankment continued to grow and should benefit from the fairly wet winter and spring. There were no erosional problems noted on the pond embankment and it appeared to remain stable. The emergency spillway also remains stable. - Sump 2 was full of what looked like mostly sediment but was not discharging at the time of the inspection. The sump will need to be cleaned. - Sump 3 contained water approximately six inches from the top and was not discharging at the time of the inspection. The sump was stable at the time of the inspection. - Sump 4 was full of sediment and was not discharging at the time of the inspection. The sump will need to be cleaned. - Sump 5 contained water to the top of the sump but did not appear to be discharging at the time of the inspection. The sump appeared to be stable at the time of the inspection. - The ditch that runs from the culvert (under the haul road to the Gossard Loadout) to Sump 5 was full of sediment. This ditch will noed to be cleaned out. Backfilling and Grading: - The Division has approved a backfilling and grading schedule for the West Pit with the 22 April 2009 approval of Technical Revision 79, The Division is currently reviewing a backfilling and grading schedule for the remaining East Pit with the Colowyo submittal of Technical Revision 80. - Colowyo has not completed any backfilling and grading in the East Pit since around January 2009, when they did some highwall reduction work with the 101 dragline. - The operator has been performing backfilling and grading operations in the Section 4 area of the West Pit (by the East Taylor Pond). This area was being backfilled by dumping material into the pit area. A portion of the northern-most area (closest to the East Taylor Pond) appears to be at or close to AOC. The operator indicated that as early as May 2009 the 102 dragline will be taken out of sequence in the West Pit and used to perform/complete some of the backfilling and grading activities in this area. It has also been discussed to use the 102 on Hink's Peak.