Laserfiche WebLink
PERMIT#: M-1985-029 <br /> INSPECTOR'S INITIALS:MAC <br /> INSPECTION DATE: October 3,2014 <br /> to install an alternate diversion point on the Middle Fork of the South Platte River. A pump house was installed <br /> at the alternate diversion point, which is located on the north side of the river adjacent to the main entrance. <br /> The pump was running at the time of the inspection and water was being pumped from the alternate <br /> diversion point to the processing building via a 12" pipe. As water is discharged from the processing building it <br /> enters a series of three settling ponds before discharging into Pond 4, the last in a series of four settling ponds <br /> which is located immediately north of the pump house. Water from Pond 4 is re-circulated back to the <br /> processing building or is discharged through an overflow pipe on the east side of the pond. The Division <br /> observed water discharging from Pond 4 into a series of shallow settling ponds located on the east side of the <br /> access road. The wash water then infiltrates into the alluvium or evaporates. Water from the pump house is <br /> directed to either Pond 4 or the processing building; the direction of the flow of water is controlled by a valve <br /> in the water line located on the east side of Pond 4. The discharge pipe into Pond 4 is situated at an elevation <br /> below that of the overflow pipe. The Division inspected the earthen dam located on the south side of Ponds 3 <br /> and 4; the earthen dam did not show any signs of failure or overtopping. <br /> The water in the settling ponds contained a significant amount of sediment and fines. According to the <br /> Operator, the water in Pond 4 is typically much cleaner than what the Division observed. The upper settling <br /> ponds are periodically cleaned out using a backhoe. Ponds 3 and 4 are too large to clean out mechanically. The <br /> Operator was in the process of setting up a floating dredge to clean the sediment from Ponds 3 and 4. The <br /> fines are salvaged and stockpiled for use during final reclamation. <br /> Off-site Damage: <br /> The Division, along with the mine personnel, proceeded to inspect the Middle Fork of the South Platte River. <br /> The section of the river immediately on the south side of the mine site contained clear water. The water <br /> started to become turbid approximately 0.3 miles downstream from the location of the pump house. As noted <br /> above, the Division inspected approximately 0.6 miles of the river downstream from the Alma Placer Mine. <br /> The water became increasingly turbid as the distance from the mine site increased and a substantial amount <br /> of fines could be seen on the river bed and on the banks of the river. While inspecting the river, the Division <br /> met with Mark Lamb, Division Wildlife Manger with Colorado Parks and Wildlife (CPW). Mr. Lamb was <br /> responding to the incident and was meeting with a fish biologist to assess the impact of the sediment on fish <br /> in the river. Mr. Lamb later informed the Division that they did not observe any immediate impacts to fish in <br /> the river. Both sides of the river were inspected in an effort to identify potential sources of the sediment. <br /> While inspecting an area of the river downstream from the mine site, the Division was contacted by Mr. Lamb <br /> who was at a different location upstream and adjacent to the pump house. Mr. Lamb notified the Division that <br /> he observed sediment and wash fines on the banks of the river near the pump house. <br /> The Division returned to the mine site to inspect the area of the river adjacent to the pump house. While <br /> traversing the north side of the river bank, the Division observed a pipe which extended into the river. The <br /> Operator informed the Division the pipe was the intake pipe for the alternate diversion point. Initially, the <br /> Division had been informed the water was pumped through the alluvium rather than directly from the river. <br /> The inflow of water into the pipe had created a small pool on the bank of the river. The Division observed fines <br /> on the bottom and sides of the pool, but did not observe any fines immediately downstream on the river <br /> bank. The Operator informed the Division there was a check valve in the water line which would prevent back- <br /> flow through the intake pipe. However, the Operator was unsure of the exact location of the check valve. <br /> Page 3 of 11 <br />