Characterization and management of waste stone dust – a case study

A thick-bedded biomicritic limestone, known commercially as Giallo d'Istria, is exploited on several locations on the Istrian peninsula. The long-established production of dimension stone in this area generates considerable amounts of stone waste. One stream of stone dust is produced during the extraction of dimension stone in quarries or underground mines. The other stream is the product of stone processing plants. Both streams are accumulated within the active mine as deposits on the surface and represent an environmental and financial burden for the company, especially due to the fact that the mine operates in one of the most famous tourist regions of the Republic of Croatia. The average annual production of commercially valuable natural stone is 38000 cubic meters of blocks per year. Due to the specific natural geological setting and exploitation method, the losses in the production and processing phase are also inevitable, giving an average amount of 9000 cubic meters of stone waste per year. This research involved determination of physical, index and design properties of waste stone dust. Waste stone dust is classified according to the unified soil classification system and also according to the tailings classification system, as the natural mineral raw material is exposed to the changes of its properties during exploitation and afterwards processing. Design parameters are also determined for the safety analyses of waste spoil heaps and for the evaluation of the waste stone dust potential use as the backfill material.