_INSPECTION - C1981019 (45) - Laserfiche WebLink

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Colowyo C-1981-019 18 May 10 Pg 417 Hydrologic Balance (cost.): - Sump 2 contained a small amount of water(approximately one foot below the top of the sump) and was not discharging. This sump was partially cleaned but a large amount of sediment remains in the sump. The sump appeared to be stable at the time of the inspection. - Sump 3 contained water approximately one foot below the top and was not discharging. - -The sump appeared to be stable at the time of the inspection. Sump 4 was full of sediment and needs to be cleaned. There was no water in the sump besides what has saturated the sediment. The sump appeared to be stable at the time of the inspection. Colowyo has removed a portion of the fence to clean the sump. -Sump 5 was full but did not appear to be discharging at the time of the inspection. The sump appeared to be stable. Colowyo is planning on cleaning this sump once it dries out. NOTE: These sumps are considered best management practices for controlling "...additional contributions of suspended solids to stream flow or to runoff outside the permit area..." They are required pursuant to Rule 4.03.1(1)(b). Backfilling and Grading: - During the inspection I discussed the backfilling and grading plan with Kurtis Blunt and Jennifer Sekulski-Barton. Colowyo plans to reclaim a portion of the West Pit just south of Hink's Peak in 2011 (approximately 130 acres) and then backfill and regrade Hink's Peak and the immediate area (approximately 120 acres) in late 2011 into 2012. While the Division likes this approach, Colowyo is reminded that all of the 2012 areas shown on Map 29 - Spoil Grading-South Area, must be completed (backfilled and regraded, topsoiled and reseeded) by the end of 2012 (approximately 676 acres). To date Colowyo has completed 51 .3 acres of B&G in the West Pit, with approximately 100 acres scheduled for B&G in 2010. Based on those acreages, Colowyo will have approximately 151 acres of B&G completed in the West Pit and approximately 525 acres of B&G remaining to be completed in the West Pit prior to the end of 2012. With the planned approximately 250 acres in 2011 and 2012, Colowyo will complete approximately 400 acres of B&G by 2012. This will leave Colowyo approximately 275 acres short of their B&G plan, as shown on Map 29. As the Division has discussed with Colowyo, in general the Division is allowing Colowyo the flexibility to complete their backfilling and grading where it best fits into their mining sequence (which is why the Division has allowed blocks of years for reclamation vs. single years, as shown on Map 29). The part of,the plan that is NOT flexible is the required number of acres of total B&G that is to be completed in the West Pit prior to (the end of) 2012, which is 675.8 acres. - Colowyo has not conducted any backfilling and grading operations in either the East Pit or West Pit since the March 2010 inspection. Colowyo has completed some of the 2010 backfilling in the West Pit but has not yet constructed the post-mining drainage channels in that reclamation area. Colowyo is reminded that all permanent, post-mining channels must be constructed based on the approved plan, as shown on Map 41 and in Exhibit 7. - The West Pit area that was backfilled, graded, topsoiled and seeded in 2009 was mostly dry at the time of the inspection. For the most part this newly reclaimed area has held up well through the winter and runoff season. There are some minor rills on some areas of the reclamation that will need to be fixed. These rills are generally less than four inches deep.