Synthetic components of aggregate mixtures usually contains waste from mining (eg. waste from coal mines), energetics (fly ash, slag), metallurgy - slags and wastes from magnesia-chromite products. Aggregates produced with the addition of steel slags often swell, which is a consequence of phases presence in aggregates composition and the process of their decomposition in water and crystallize secondary phases. This phenomenon may cause a potential local groundwater pollution because Ta, V, Mo and Cr ions may be leaching from glass and srebrodolskite (components of metallurgical slags,) and Cr(VI) from magnesia-chromite wastes.