Van Dieman Mines has announced a revised development plan for its two tin and sapphire mine projects in Tasmania. This followed a two month review of the projects by a newly-appointed operations director. The Scotia mine is now expected to begin commissioning in July and reach full production by the end of the year, while the Endurance project is still on track to start up in early 2009. The two operations are expected to produce 1,200 tpy of tin-in-concentrate over a 10 year life.
In a statement the company said that “The main findings of the operational review were that the proposed mining methods and significant components of the original process plant design for Scotia (and also planned for Endurance) were inappropriate, given the water-saturated characteristics encountered in initial pre-stripping of the overburden and pre-commissioning of the process plant.” As a result various changes are now planned, including the trialling of alternative ore transport systems and modifications to the concentrator plant. However the company believed that the changes will reduce capex by A$4 – 6 million and could also reduce operating costs.
The review also concluded that “the basis upon which the previous management team determined the JORC reserves and resources was not consistent with current best practice. This is largely because of the almost total reliance on drilling data that is 70 to 100 years old. The Board, therefore, considers it prudent to embark on a limited (5,000 m) confirmatory drilling programme to validate the previously determined JORC reserves. The drilling program will also provide information to fine-tune mining options, assist with dewatering, and enhance mine planning. The proposed drilling programme will initially focus on the Scotia Project resource and will take about 4 to 6 months and A$0.5 million to complete.”
