GEOCHEMICAL DISTRIBUTION OF POTENTIALLY TOXIC ELEMENTS FROM A REHABILITATED MINE DUMP AND THE INFLUENCE ON VEGETATION. STUDY CASE OSTRA MINING AREA, ROMANIA

This study aims at accomplishing a geochemical distribution of potentially toxic elements (PTEs As, Co, Cr, Ni, Pb and Mn) in the dumps material. In 2014, from the Ostra mine, some dump anthropogenic material and plant samples were taken from 14 points having been regularly distributed on the surface of the dump. Its purpose is the assessment of the state of the environment 10 years after rehabilitation works through the study of the PTEs concentrations. The accumulation of the mobile forms of PTEs in vegetation was determined for several different species (Cirsium rivulare, Deschampsia flexuosa, Alnus glutinosa, Picea abies, Urtica dioica) and plant parts (root, stem, leaf). The vegetation samples were grounded in an agate mortar, digested in a MARS 6 closed vessel system and analysed by Agilent 7700x ICP-MS. The related outcomes have been statistically processed with a view to obtain a geodatabase which could help creating distribution maps for each PTE with the aid of the GIS software.