ScoZinc Mining, a Canadian base metals exploration and development company, plans to restart its wholly-owned ScoZinc zinc-lead mine near Halifax in central Nova Scotia, Canada.
The ScoZinc mine, also known as the Gays River deposit, was discovered by Cuvier Mines and Esso minerals in 1973.
Acadian Mining Corporation purchased the mine from HudBay in April 2006 and commenced operation in mid-2007.
The mine was, however, put in care and maintenance in early-2009 due to the worldwide dip in zinc and lead prices.
Selwyn Resources (now ScoZinc) bought the mine in June 2011 and released a preliminary economic assessment (PEA) for the potential restart of the mine in August 2011.
The company has been engaged in further economic and technical optimization studies for the restart project since then.
The updated PEA announced in October 2018 forecasts a 3,000tpd mill throughput operation over an estimated mine life of 6.4 years.
ScoZinc has already invested $7.6m in engineering, definition drilling, permitting, and mill and mine infrastructure refurbishment as well as surface rights acquisition for the mine restart project.
It requires an estimated additional capital of $20m to restart the mine.
Off-take and financing agreements for the ScoZinc mine
ScoZinc entered a strategic off-take and financing agreement with MRI Trading for the mine restart project in April 2018.
MRI agreed to off-take the lead and zinc concentrates to be produced throughout the life of ScoZinc mine and provide $10.6m of debt and $0.76m of equity capital for the project.
Geology and mineralization
The ScoZinc property comprises 12,256 hectares of prospective mineral claims within the Carboniferous limestone reef on the edges of the Windsor Basin in Nova Scotia.
The two major carbonate rock formations occurring in the region are the Gays River Formation and the MacCumber Formation.
ScoZinc mineral reserves
The ScoZinc mine was estimated to hold 12.2 million tonnes (Mt) of measured and indicated mineral resources grading 2.76% zinc, 1.6% lead, and 4.68% zinc-equivalent.
Inferred resources were estimated to be 4.64 Mt grading 2.22% zinc, 1.53% lead, and 4.05% zinc-equivalent.
Mining and processing at the ScoZinc mine
Sequential open-pit and underground mining methods are proposed for the ScoZinc mine development.
The open-pit ore resources will be extracted with drill, blast, truck and shovel operations, whereas the underground ore will be extracted employing cut-and-fill mining method with uncemented backfill.
The mine is expected to provide an average 990,000t of mill feed a year. The stock-pile ore will be processed in the onsite ScoZinc processing plant, which was constructed by Canada Wide Mines in the late-1970s.
The mine restart plan includes redesign and replacement of the crushing circuit, primary screen, thickeners, and concentrate filters at the processing plant.
ScoZinc has already acquired a semi-autogenous (SAG) mill to install at the processing facility.
The crushed and grinded ore will further undergo froth flotation and concentrate thickening to produce zinc and lead concentrates.
The concentrates produced by the mine will be sent to ScoZinc’s own storage and concentrate loading facility for shipping at Sheet Harbour, Nova Scotia, located approximately 80km away from the mine site.
Infrastructure facilities for ScoZinc mine
The ScoZinc mine, located 55km north-east of Halifax, is directly accessible from the Highways 277 and 244.
The water requirement for the mine will be met through the in-process recycled water as well as the water pumped from the nearby Gays River.
Electricity will be supplied through an existing 25kV power line from the Emsdale sub-station.
Contractors involved with ScoZinc mine restart
Dexter Construction and Dyno Nobel Canada were selected as the mining and drill/blast contractors for the ScoZinc mine restart, in February 2018.
Stantec Consulting was engaged for preparing the preliminary economic assessment (PEA) for the restart of ScoZinc mine.