2018-08-31_GENERAL DOCUMENTS - M1977493

Home Browse Search

2016 Reclamation Cost Estimate Update — Climax Mine 300,000 cy of sediment and sludge to expose a native footprint around the margins of the lake to encourage development of hydric vegetation communities. These areas will also be seeded with the hydric seed mixture. The AM -06 cost for this project area included some general work items such as mobilization and demobilization, and sediment and erosion control. This update includes these general costs grouped for all areas (see Sections 2.20 and 2.27). 2.17 5 Dam 5 Dam has been reclaimed in its current configuration. However, an increase in the height of 5 Dam during the course of the current production operations will create up to 59 acres of tailing which will require reclamation at the completion of dam construction. A nominal 12 inches of growth medium (6 inches of biosolids or topsoil over 6 inches of subsoil) will be applied to these 59 acres of the dam face for a total of approximately 95,000 cy. The upland standard seed mixture will be applied to the cover material. The AM -06 cost for this project area included an incorrect cost basis for the cover thickness which was not consistent with the reclamation plan described in Exhibit E. This update reflects the corrected cost basis and calculation. 2.18 Revegetation Revegetation activities which follow the proven guidelines provided in AM -06 will be followed. Overall acreages of impacted footprints have increased slightly. However, several successful reseeding projects have been conducted by Climax since the submittal of AM -06 for which more cost effective techniques have been successfully utilized. These have resulted in lower unit rates which are reflected in the updated reclamation cost estimate for the seeding of all regraded slopes. This cost will include seeding, mulching, and crimping site wide, an area of approximately 2,500 acres or almost 4 square miles. 2.19 Seal Underground Mine Openings No. 3 Gallery is currently blocked off to prevent access. Upon cessation of mining operations, it would require further work to prevent long-term access. A 2 -feet thick concrete bulkhead is proposed for the No. 3 Gallery closure. Storke Portal currently has ventilation access to the 600 level of the underground workings. Similarly, upon cessation of mining operations, it would require further work to prevent long- term access. A 2 -feet thick concrete bulkhead is proposed for the Storke Portal closure. Unit rates for the concrete bulkheads have been updated using RS Means 2016 references. The Phillipson Portal will be closed at cessation of mining but since it will be sealed easily with minor use of a bulldozer its cost is considered insignificant. 2.20 Mobilize and Demobilize Prior reclamation cost estimates included a minimal total cost for total project equipment mobilization and demobilization. For this cost estimate update, we have assumed annual mobilization and demobilization lump sum costs based on historic Climax reclamation projects for a period of four years. 2.21 Buffer Zone The Buffer Zone reclamation is a DRMS-required reclamation cost and remains fixed from the AM -06 value. 2.22 Hydrologic Protection Water management and site -wide water treatment will continue at Climax long after the cessation of production operations. The AM -06 reclamation cost estimate for hydrologic protection has been updated using current values for 2013-2016, which are now reflective of a successfully operating downstream water treatment facility, the PDWTP. All previous unit rates have been updated using current data from the 2013-2016 YTD operating period (8/31/16) with lime costs perhaps increasing the most over the AM - 06 estimate. An additional line item has been added for Outside Services and the number of Water 5 November 2016 (revised August 2018)