Materiały konferencyjne SEP 2025

7 The significant impact categories for New Kankberg case are: Urban land occupation, Natural land transformation, Fossil depletion. Within the category Urban land occupation positive and negative impacts are almost equal. The positive impact on the environment (negative value) results from avoiding landfilling of gold tailings. On the other hand, tailings after REEs benefi- ciation are disposed at the tailing pond designed for gold tailings. Tailings quantity and quality is almost unchanged by beneficiation process. The fossil depletion category indicator is de- pendent on the consumption of fossil fuels (crude oil for petroleum production, natural gas and hard coal) for electricity production and fuel for transport. The results of LCA modelling for production of REEs concentrate from Covas tailings is shown in figure 5. The significant impact categories for Covas case are: Fossil depletion, Climate change Human Health, Climate change ecosystem, Urban land occupation. High value of Fossil depletion cat- egory indicator results from electricity production from fossil fuels (coal, natural gas, crude oil) as well as fuel for transport purposes. The high values in Climate change categories are caused mainly by carbon dioxide emissions from the production of electricity from fossil fuels and lime production for acidity reduction in land reclamation. Within the category Urban land oc- cupation positive and negative impacts are almost equal. The positive impact on the environ- ment in Urban land occupation (value below zero) results from avoided impact, that is taking from the environmental the old mine tungsten tailings. The negative impact (value above zero) is caused by disposal residues after REEs beneficiation process. Figure 5. LCA results of the production of REEs concentrate from Covas tailings [9].