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Abstract: The aim of this paper is to establish the abundance of heavy metals in the soils affected by the past Rosia Montana gold and silver ore mining, and in currently unaffected soils that will be impacted by the proposed Rosia Montana project that foresees the expansion of the ore exploitation and a new processing facility. The soil cover of the Rosia Montana area consists of five soil types: Eutricambosols, Districambosols, Regosols, Lithosols, and Aluviosols. The first two types are prevalent; they cover 73.83% of the total researched surface (1,646 ha). In the soils from the areas where mining activities have been carried out, the total content of the heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) vary from the region’s pedogeochemical background level up to the alert threshold for heavy metals pollution set down in the Order of the Ministry of Waters, Forests, and Environment Protection no. 756/1997. The analysis of soils from and surrounding the existing ore processing facilities shows that the heavy metals contents in few cases is above the intervention threshold, for copper, lead and zinc. The soils generally have low heavy metals contents and the values are at the region’s pedogeochemical background level. The barren rocks, generally, have low heavy metals contents, close to the clark values. Taking all this into account, as well as the technology that the Canadian company intends to apply, there is a low probability that a significant heavy metals pollution of the soils left un-stripped would occur due to the proposed project.

Keyword: mining activities, auriferous ore, heavy metals, abundance index, pedogeochemical background