2012-04-02_REPORT - C1982057 (9)

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Weed Control A survey for noxious weeds was carried out on the II -W mine area in the spring of 2011. Monitoring was conducted to determine the need or level of re- treatment necessary for the areas sprayed in 2011. Canada thistle was the primary target species in all control areas, with lesser activity directed toward areas of hounds tongue and whitetop. The applied herbicide consisted of a tank mix of 2.5 gallons of 22K Tordon and 2.5 gallons of 2,4,D and 250 gallons of water. Escort, at the rate of one (1) ounce per acre was spot sprayed on whitetop. Control areas were sprayed in June, July, and August. See the attached 2011 Weed Spray Location map for the extent of weed control spraying. A spot spray gun was used to concentrate spraying activities on target areas, reducing potential impacts to adjacent desirable vegetation. The herbicide mix, based on recommendations from the Colorado State Extension Service, was mixed and applied by an outside contractor who is a certified applicator. The weed control areas will continue to be monitored in 2012 for effectiveness and necessary retreatment. See the attached weed control daily log spreadsheet for more detailed information of the 2011 herbicide application. Actual field logs are on file at the mine site. • Grazing Cattle (172 cow /calf pairs) were moved on to the Seneca II -W reclaim area for 51 days between August 20" and October 11" This grazing scheme resulted in a total of 349 AUMs for 2011. See attached 2011 Grazing Plan Map. Assumptions: One (1) cow /calf pair = 1.0 AUM One (1) AUM requires 810 lbs. of forage 51 days (x) 172 cow /calf pairs = 8,772/30 days = 292.2 animal unit months (AUMs) 1,500 lbs /acre (x) 685.2 acres = 1,027,800 lbs of forage available 810 lbs (x) 292.2 AUMs = 236,682 lbs of forage required Therefore; 236,682/1,027,800 (x) 100 =23 % utilization of the Seneca II -W reclaim area. CHRONOLOGICAL HISTORY OF REVEGETATION Total areas revegetated prior to and in 2011 at the Seneca II -W Mine are shown on the attached 2011 Chronological Seeding map. SEDIMENTATION POND SURVEYS SCC is required by Permit C -82 -057 to monitor sedimentation ponds for sediment storage capacities. This monitoring is conducted by physically surveying each pond each year. This schedule provides a sediment yield history and gives advanced warning to operations personnel when sediment clean out work is needed. Also, in accordance with Rule 4.05.6(11)(c), SCC visually 3