Optimisation work to determine the optimum production plan for the Parys Mountain copper/lead/zinc project, on the island of Anglesey, north Wales, is moving steadily ahead, with results expected by the end of the year.
The objective of the optimisation study, undertaken by QME at no cost to project owner Anglesey Mining, is to determine a production plan for the mine using available and potential means of accessing the indicated resources and inferred resources, at various cutoff grades.
In its preliminary work to date, QME has identified the potential for improvements in the development plans contained in the 2017 scoping study, which was based on mining only the 2.1-million tonnes of indicated resources reported by Micon in 2012. Micon had reported a further 4.1-million tonnes of inferred resources that were not incorporated into the scoping study.
Anglesey said on Wednesday that the QME studies had suggested that the project could be further improved if the potential mineable tonnage could be increased by using a lower cutoff grade and generating a revised mine development plan.
“This second stage of the process is ongoing with completion scheduled for the end of 2019. Subject to financing being available, this work would then form the basis for commissioning an updated scoping or preliminary feasibility study,” the London-listed company said.
The 2017 scoping study on the Parys Mountain was prepared by Micon and Fairport Engineering. The study envisages a mining rate of 1 000 t/d, to produce an average of 14 000 t/y of zinc concentrate at 57% zinc, 7 200 t/y of lead concentrate at 52% lead and 4 000 t/y of copper concentrate at 25% copper, over an initial mine life of eight years.
Although the scoping study demonstrates a viable mine development and a healthy financial rate of return based on copper prices of $2.50/lb, zinc prices of $1.25/lb and lead prices of $1.00/lb, generating an overall net smelter return of $270-million with an internal rate of return of 28% and a net present value, at a 10% discount, of $43-million, the study recommended further work as interim steps towards undertaking a feasibility study. This included more detailed mine planning and design, more engineering studies, additional metallurgical testwork and a review of tailings management and environmental and planning permissions.
Following delivery of the optimisation studies, and the subsequent completion of a feasibility study, QME would have the option to undertake at QME’s investment, the mine development component of the Parys Mountain project, including decline and related underground development and shaft development, in consideration of which QME would earn a 30% undivided joint venture interest in the project.
If exercised, this would significantly reduce the capital cost to the group for the development of the mine.