Tailings stored in the studied impoundments were found to be contaminated with some hazardous/ priority hazardous metals, fluoride and sulphate and thus presents different contamination risk for the environment.
The priority hazardous metals (Cd, Pb and Ni) and Co were not taken under consideration for soil characterization as their concentrations were below the detection limits (mg/kg): 1.70 Cd, 50 Pb, 12 Ni and 1.70 Co in any samples.
His scientific interests relate to monitoring of the priority hazardous metals in environmental samples and different materials, as well as development of analytical methods using instrumentation based on plasma microtorches.
The third component (PC3) of 11% variability was assigned to priority hazardous (Pb) and hazardous metals (Cr) as well as ions (F-, SO42-, NH4+) leached from oxidized S-containing minerals (Fe and Ca sulphates).
These minerals constitute the main contamination source of soil and water in surrounding areas with hazardous (As, Zn) and priority hazardous (Cd, Pb) metals resulted from sulphide oxidation and dissolution of soluble sulphates.
Cadmium (Cd) is one of the biologically nonessential, nonbiodegradable, persistent type of priority hazardous and heavy metal pollutants (Campbell 2006), which easily accumulates in sediments and aquatic organisms (by bioaccumulation and biomagnifications), and thus causing a gross biological impact.
The first component (PC1) accounting for 61% variability was associated to priority hazardous (Cd, Ni) and hazardous (Cu, Co, Cr, Zn) metals as well as Mn and anions (F-, SO42-) retained on Al and Mg minerals leached in water.
Other hazardous metals commonly encountered in industry include arsenic, beryllium, cadmium, chromium, lead, manganese, nickel, and thallium.
Data in Table 7 show that hazardous/priority hazardous metals exhibit different association to waste rocks.
Tailings of all seven impoundments present a very high contamination degree with hazardous/priority hazardous metals increasing in the order Stefanca < Gura Rosiei < Sesei < Saliste < Cutii < Sartas < Brazesti.
To highlight whether these tailings pose a contamination risk, the total and leached fraction of hazardous/priority hazardous metals and ions concentrations in leachate were taken into account.
