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The biggest sources of large-scale pollution of soil and water environment in the world are agriculture and air pollution. In urban areas and large cities, where areas are built-up, it is difficult to assess the direct impact of these factors on the quality of soils and groundwater. The possibility of substances entering the environment depends primarily on the geological structure and hydrogeological conditions; however, the main direct factors affecting water pollution in Krakow city are anthropogenic stratifications [1]. These are mainly former post-industrial pollution sources on the surface (heaps, dumps) but also the maintenance of public roads.Maintaining the road target standard, in particular, removing snow and winter slipperiness (slush) is an important aspect of any governmental budget. Annually, Polish cities allocate from a few to a dozen million zlotys for this purpose. Preparing for winter is a large logistical project, in particular the purchase and storage of road salt or the servicing of Pol. AbstractThe use of communication routes is associated with general awareness of the high environmental pollution caused by heavy metals. Research carried out on the example of the busy Opolska Street in Krakow, Poland, showed that the surrounding land is clean and does not show any signs of pollution. The geometric mean contents of metals and metalloids in the ground are as follows: for arsenic As 3+ -0.0088 mg/kg, cadmium Cd 2+ -0.0005 mg/kg, copper Cu2 + -0.0406 mg/kg, mercury Hg 2+ -0.0001 mg/kg, nickel Ni 2+ -0.0077 mg/kg, lead Pb 2+ -0.0028 mg/kg and zinc Zn 2+ -0.0160 mg/kg. The main threat to the ground and water environment was the maintenance of the road during the winter period. On a 58-m research section, after the measurement period, the amount of chlorides increased in the soil environment by over ½ kg, i.e., +561 mg/kg (+592 for December and +530 mg/kg for January). A green belt separating roadways is a permanent element of the exposed ground. The total length of Opolska Street is 3,400 m and the green belt is about 2,900 m, with an average width of 4 m along the entire length of the street. Through this section of land alone, more than 2½ tons of chlorides enter the ground and then into the shallow Quaternary groundwater. This value translates into 4 tons of road salt (NaCl rock salt).

The chemical composition of surface waters of the Przemsza River flowing through Upper Silesia (in southern Poland) is strongly affected by Zn and Pb ore, and less by Carboniferous hard coal deposits. The chemical type of surface water is Ca-HCO3. In the waters, three groups of metals and metalloids were found that directly interfere with the mineralization of the deposit. Although genetically related to the same deposit, each group exhibits a different fate in the environment. A typical deposit association is Pb-Zn-Ag-As-Sb-Hg. The first group of metals in surface waters is consistent with the typical association of the ore Zn-Pb-Cd-(Tl), the second includes Ag-Sb-Hg, and the third includes the additives in the zinc and lead ore Co-Ni-Mo-Mn:[(Ca↔Na)+(HCO3↔Cl)]+[(Zn-Pb-Cd-(Tl))+(Ag-Sb-Hg)+Co-Ni-Mo-Mn)].Depending on the pH-Eh conditions, metals and metalloids precipitate out of the solution or sorb on solid particles. The concentrations of individual groups of metals are interdependent but show different environmental fates along the river course. The natural process of the enrichment of surface waters with Zn-Pb-Cd-(Tl) is by water circulation in a rock matrix naturally rich in the metals and draining groundwaters by the river. Under oxidizing and slightly alkaline conditions, Ag-Sb-Hg incorporated into the soluted chemical compounds, may, when the physicochemical parameters of the waters change, be adsorbed and/or precipitated. The presence and ratio of concentrations of Co-Ni-Mo-Mn with respect to zinc are almost identical, differing only in concentration.

The decay of organic matter of anthropogenic origin in a highly contaminated shallow groundwater system occurs permanently regardless of the availability of oxygen. Oxidation of organic matter smoothly changes from aerobic to anaerobic and vice versa. Hydrogeochemical transformations occurring in the interior of the contaminant plume are conditioned by the position in the 3D zone of the so-called “redox reactor” and its edge. The primary reaction initiating the decay of organic matter (TOC max 1620 mg/L, phenol max 613 mg/L) is its aerobic oxidation. In the case of the consumption of free oxygen, the decay undergoes anaerobic oxidation, where the source of electrons are oxides and hydroxides (MnO2, Fe(OH)3). As a result of these reactions, mobile ions Mn2+ and Fe2+ pass into the aqueous environment creating a concentration anomaly (max 15 mg/L for Mn2+, 673 mg/L for Fe2+). The presence of Fe2+ in groundwater is crucial. A strong correlation between the organic matter decay processes and concentration of the Fe2+ showed that “iron index” may be a preliminary marker for the hydrogeochemical recognition of aquifer and allows to diagnose zones with an intense organic matter decay, especially by anaerobic oxidation through redox reactions. At the edge of the “redox reactor” redox sensitive metals (Fe2+, Mn2+ and also Cu2+, Cr3+, Hg2+) undergo aerobic oxidation due to the access of oxygen as a result of mixing of contaminated groundwater and oxygenated pure Quaternary water. These transformations produce oxides and hydroxides (MnO2, Fe(OH)3)—new reaction products, however, are used for anaerobic oxidation of organic matter. Organic matter decay is an cyclic system of redox processes up to the full decay of pollutants and generation of the anomalously high concentrations of redox sensitive metals in the ground.

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