2015-06-09_INSPECTION - M2011009

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PERMIT #: M-2011-009 INSPECTOR'S INITIALS: MAC INSPECTION DATE: May 28, 2015 OBSERVATIONS The inspection was conducted by Michael Cunningham of the Division of Reclamation, Mining and Safety (Division). Mike London and Rhonda London were present on behalf of IGWT Mining, Inc. and Greg Lewicki and Ben Miller were present on behalf of Greg Lewicki and Associates. The Hector Placer mine is located approximately one mile south of Alma, Colorado in Park County. The site is permitted for 100 acres and the post -mining land use is wildlife habitat. The primary commodity mined is gold. The primary purpose of this inspection was related to the approval of Technical Revision No. 1(TR01). The Division approved TR01 on May 21, 2015, which revised the Mining Plan to allow for the use of flocculent in the gold recovery process. Currently slurry from the sluice box enters the sluice tails pond before the water discharges into a lower settling pond. Clean water from the lower settling pond is pumped back to the sluice. The residence time in both the sluice tails pond and the lower settling pond is not adequate to allow all of the fine particles to settle out. The addition of flocculent to the process will aid in the settling of fine particles in the sluice tails pond and will result in cleaner water in the lower settling pond. The Hyperfloc AF852 solution will be added to the sluice box and will mix with the slurry as it discharges into the sluice tails pond. Active mining operations were taking place during the inspection. The Operator is currently excavating in two separate areas, approximately 1,000 feet north of the shop building. Topsoil is being stripped ahead of extraction activities and is being stockpiled to the east of the sluice tails pond. The Operator had not fully implemented the addition of flocculent to the gold recovery process at the time of the inspection. However, the Division observed flocculent in the required metal stock tank which was located adjacent to the sluice. The Operator was calibrating the equipment to achieve optimal mixing rates prior to introducing flocculent into the process. The Division traversed the perimeter of the sluice tails pond and the lower settling pond; both of the ponds were full and process water was circulating through the ponds. The ponds are oriented north to south and the ponds are divided by an access road. Water from the sluice tails pond flows through a culvert under the access road to the lower settling pond. The Division observed a small area of ponded water at the southeast corner of the lower settling pond. The Division inspected this area and found that water was seeping from two different areas. The first area of seepage was occurring at the southeast corner of the site. The water was flowing out of the side wall of the lower settling pond and through the colluvium before ponding in a low lying area. The second area of seepage was observed at the southwest corner of the site. Water was percolating from the ground in this area; the water from both seepage areas reported to the same location. Both of the seepages were discharging at less than 1 gallon per minute. All of the water is contained within the affected area and there was no immediate threat of the water leaving the site. The south end of the lower settling pond has an earthen embankment which is of insufficient height; portions of the embankment were at or near the same elevation of the water level. The area has received a substantial amount of precipitation through spring storm events, which has led to saturated ground conditions. However, the Operator is responsible for minimizing disturbances to the prevailing hydrologic balance of the affected land and to the surrounding area per Hard Rock Rule 3.1.6. In addition, a condition of the approval of TR01 is that the sluice tails pond and the lower settling pond will be sealed with fines, thus preventing any loss of process water from the ponds. The minor seepages observed around the perimeter of the lower settling pond have been cited as a problem and will require corrective Page 2 of 7