A study conducted in the Almașu Mare commune of Alba County, Romania, focused on the “Radeș” exploitation site, delving into the historical gold mining heritage of the region since 1900. The site, now abandoned, is heavily polluted with lead, copper, and other heavy metals due to improper waste storage and acid mine drainage.
Researchers collected samples of gangue material from the area and found alarming concentrations of lead and copper that exceeded legal thresholds. To mitigate this environmental hazard, an experimental model of phytoremediation using Robinia pseudoacacia was implemented at the laboratory level.
The study involved different stages, including the preparation of experimental variants by mixing sterile material from the dump with soil and dewatered sludge, sowing Robinia pseudoacacia seeds in the prepared pots, and applying watering with potassium monobasic phosphate and enzyme solutions. The concentrations of lead and copper in plant tissues and roots were determined using atomic absorption spectrophotometry.
The bioconcentration and translocation factors were calculated to assess the plant’s ability to extract heavy metals from the soil. The results indicated the potential of Robinia pseudoacacia for phytoremediation, with bioconcentration and translocation factors exceeding 1, making it suitable for phytoextraction.
Overall, the study provided valuable insights into the effectiveness of phytoremediation in addressing heavy metal pollution in abandoned mining sites, offering a sustainable solution to remediate contaminated environments and protect human health.