Woulfe Mining Corp has announced a revised mineral resource estimate for its Sangdong Tungsten Project. The company determined, after a detailed review during 2013 that it was urgent and necessary to reassess and de-risk the 2012 TetraTech feasibility study of the project.
To this end, Woulfe embarked on an additional phase 5, closely-spaced grid drilling program, which started in April 2014 and was completed in August 2014. The recent drilling program added 11,340 metres of resource definition drilling to the data available for the 2012 TetraTech study.
In addition to the drilling program, an important and necessary geotechnical study was carried out by Turner Mining and Geotechnical during June and July 2014, using a database that increased from 22 to more than 400 geotechnically-logged boreholes. The 2014 drilling program, combined with an enhanced geotechnical database, provides satisfactory input for the completion of a revised feasibility study which is expected to be released by the end of 2014.
Woulfe commissioned AMC Consultants of Melbourne, Australia, in August 2014 to undertake a mineral resource update to be reported in accordance with NI 43-101 for the Sangdong property. This study was based on the additional available data.
AMC confirms measured and indicated resources at a plus 0.4% cut-off grade of 3.81 million tonnes at a grade of 0.56% WO3 containing 21,336 tonnes of metal. The AMC Report also reports substantially less inferred resources compared to the TetraTech study when using the same cut-off grade used by TetraTech, which was 0.15%. It confirms 11.28 million inferred tonnes @ 0.64% for more than 71,000 tonnes of metal.
The 2012 study produced resource estimates at a cut-off grade of 0.15% WO3 based on a bulk mining approach contemplated at that time. By comparison, the AMC Report uses a cut-off grade of 0.4% WO3 based on a more selective mining approach currently being considered.
The first phase of development will be focused between Level -1 to the Taebaek Level which are three immediately reachable levels above a further 15 levels to be de-watered progressively after start-up of operations, which all represent reasonable prospects of eventual economic extraction.
AMC recommends that Woulfe continue to investigate the lower levels down to -16 Level as the mine is progressively de-watered in the future, and to grid drill the thicker part of the Hanging Wall Mineralization from the -1 to Taebaek levels, which represents 75% of the inferred resources and contains widely spaced historic drill intersections containing plus 0.5% WO3 across 10-plus metres. Grid drilling of the Hanging Wall Mineralization commenced in late September 2014 and is expected to finish during November 2014.
Woulfe is now developing a revised mining plan adapted to the mineral resource model established by AMC. The new mining plan is anticipated to be substantially different from the 2012 feasibility study. The plan is expected to be completed by early November and will be an important building block in the finalization of the revised study.