Matthews, D 2015, 'Pillar design around mullock-filled stopes in the 3500 Orebody, Mount Isa Mines', in Y Potvin (ed.), Design Methods 2015: Proceedings of the International Seminar on Design Methods in Underground Mining, Australian Centre for Geomechanics, Perth, pp. 257-272, https://doi.org/10.36487/ACG_rep/1511_14_Matthews
(https://papers.acg.uwa.edu.au/p/1511_14_Matthews/)
Abstract: A two-lift stoping strategy was determined to extract ore close to a previously extracted mullockfilled stope leaving as small a pillar as possible. On successful extraction of the stope, the strategy was adopted for the rest of the retreat using the pillar vertical height to thickness ratio to assess pillar stability when other more generic pillar stability assessment methods predicted unstable pillars.

This method has also been applied to the southern 3000 Orebody to justify the extraction of ore previously thought to be sterilised.