Closure with Ecological Engineering of a Remote Cu/Zn Concentrator: Overview of 10 Years RD Field Program

摘要

A 15 year field investigation to rehabilitate a small (0.75 million t) remote mining property using Ecological Engineering is described. The effluents from mill and tailings deposit (41 % pyrite, 4% pyrrhotite) represent 15 t.y~(-1) of zinc in AMD. The AMD was redirected to a 1 million m~3 lake, serving as a polishing pond. Ecological Engineering measures consisted of adding brush, phosphate, and calcium nitrate to the lake water and or the sediments. The biological activity, enhanced by these measures, retains 80% of the zinc load within the polishing pond. The capital costs for a conventional high-density treatment plant were estimated at $CDN 2.5 million with annual operating costs of $0.35 million. To date, the annual costs of the Ecological Engineering approach are $0.17 million.