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Project Completion Inspection 3 November 11, 1999 <br /> Upland Hydrologic Control Project CDPS No. CO-0044768 <br /> Consent Decree 94CV5459 DMG File No. M-77-378 <br /> two manhole drains was backfilled with rock cover. The manhole covers safeguard the <br /> drop structures and serve as debris guards for the culvert inlet. Water could be heard <br /> entering the culvert. Discharge from the outlet of diversion B appeared consistent with <br /> inflow, little more than a trickle. Large rock were appropriately placed at the culvert outlet <br /> as energy dissipators. Construction of upland diversion B appeared complete, affected <br /> areas had been graded to blend with surrounding topography and reseeded. Surface of <br /> affected areas had been stabilized by replacement of native talus material. <br /> Upland Diversion C is located in an upland drainage and directs shallow subsurface flow <br /> and surface runoff around the east side of the Mayflower Mill and associated affected <br /> areas. Diversion C was constructed within a pre-existing drainage channel and on talus <br /> slopes and therefore minimized disturbances to native vegetation created by culvert <br /> installation. Diversion C is a buried 24" diameter culvert, approximately 600' long. The <br /> culvert material is a double walled black plastic pipe, the outer wall is annular ringed, the <br /> inner wall is smooth. One 48" diameter manhole was set in the bottom of a concrete lined <br /> catchment bowl to direct drainage into the culvert inlet. Rebar cage secured the opening <br /> of the manhole and serves as a debris guard for the culvert inlet. Water could be heard <br /> entering the culvert. Discharge from the outlet of diversion C was significant and appeared <br /> consistent with inflow. Large rock were appropriately placed at the culvert outlet as <br /> energy dissipators. A second manhole was located approximately 150' downslope from <br /> the culvert inlet. The second manhole was secured by locked cover and provides access <br /> into the culvert for maintenance purposes. Construction of upland diversion C appeared <br /> complete, affected areas had been graded to blend with surrounding topography and <br /> reseeded. Affected areas appeared stable, evidence of slope movement, excessive erosion <br /> or sediment deposition was not observed. <br /> Conclusion: Installation of the diversion structures and reclamation of associated affected <br /> lands appeared consistent with SGC's October 14, 1999 submittal, and appeared to have <br /> been completed in accordance with the conditions of the Consent Decree and in <br /> accordance with the performance requirements of the Colorado Mined Land Reclamation <br /> Act and the Hard Rock/Metal Mining Rules and Regulations of the Colorado Mined Land <br /> Reclamation Board. <br /> Attachment: Copy of SGC's report to WQCD, submitted to DMG on 10/14/99; and <br /> Copy of map showing approximate locations of the diversion structures <br /> cc: Allen Sorenson, DMG <br />