No abstract

Express roads are a potential source of heavy metal contamination in the surrounding environment. The Warsaw Expressway (E30) is one of the busiest roads in the capital of Poland and cuts through the ecologically valuable area (Mazowiecki Natural Landscape Park). Soil samples were collected at distances of 0.5, 4.5 and 25 m from the expressway. The concentrations of cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) were determined in the soils by the flame atomic absorption spectrometry method (FAAS). Soils located in the direct proximity of the analyzed stretch of road were found to have the highest values of pH and electrical conductivity (EC), which decreased along with an increase in the distance from the expressway. The contents of Cd, Cu and Zn were found to be higher than Polish national averages, whereas the average values of Ni and Pb were not exceeded. The pollution level was estimated based on the geo-accumulation index (Igeo), and the pollution index (PI). The results of Igeo and PI indexes revealed the following orders: Cu < Zn < Ni < Cd < Pb and Cu < Ni < Cd < Zn < Pb, and comparison with geochemical background values showed higher concentration of zinc, lead and cadmium.

Application of permeable reactive barriers near roads for chloride ions removal.One of the most critical sources of pollutants are road run-offs. Road run-off is a complex mixture of toxicants e.g. heavy metals, de-icing agents, organic compounds and water suspensions of solid substances. One of the most negative impact on the environment has sodium chloride which is used as de-icing agent. In the case of incorrect environment protection in the vicinity of roads pollutants may migrate to groundwater causing hazard to sources of potable water. One of the methods to prevent the migration of pollutants to groundwater is imposing the fl ow of polluted water through a reactive material fi lling a permeable reactive barrier (PRB). This paper examines the feasibility of selected reactive materials for the reduction chlorides concentration in road run-offs. Four different reactive materials: zero valent-iron, activated carbon, zeolite and geza rock have been chosen for studies. The tests results indicated that the most popular reactive materials used in PRB technology, activated carbon and zero-valent iron, removed exhibited the highest effi ciency in chloride ions removal. Moreover, the composition of road run-off in samples collected along roads in Warsaw was determinated.

This article focuses on the impact of fly ash from the combustion of municipal sewage sludge (FAMSS) as a cement additive in the amounts of 5%, 10%, 15%, 20% and 25% (by mass) on selected concrete properties. In the course of the experimental work, water penetration depth and compressive strength measurements were made at various periods of curing (from 2 to 365 days). In addition, the potential impact of FAMSS on the natural environment was examined by determining the leachability of heavy metals. FAMSS-modified concretes showed small values of water penetration depth (lower than 50 mm), as well as good compressive strength (reaching minimum class C30/37 after 130 days of maturing)—similar to the compressive strength obtained for conventional concrete. In addition, the partial replacement of cement with FAMSS has environmental benefits, expressed as a reduction in CO2 emissions. In addition, study has shown that compliance with environmental requirements is associated with heavy metal leaching.

The effects of increasing nickel contamination of soil on the update of selected microelements by Brassica juncea L. in the presence of raw halloysite (RH) and halloysite modified by thermal treatment (calcination) at 650°C (MH) were investigated experimentally. Such treatment causes partial dehydroxylation and enhances mineral-adsorption properties towards cations. In a vegetative-pot experiment, four different levels of Ni contamination, i.e. 0 (control), 80, 160, 240 and 320 mg kg−1 were applied in the form of an analytical-grade NiSO4·7H2O solution mixed thoroughly with the soil. Among the minerals which were added to soil to alleviate the negative impact of Ni on plant biomass, MH had a particularly beneficial effect on the growth of B. juncea L. The amount of Ni, Zn, Cu, Mn, Pb and Cr in Indian mustard depended on the Ni dose and type of accompanying mineral structure. The average accumulation of trace elements in B. juncea L. grown in Ni-contaminated soil follow the decreasing order Mn > Zn > Cu > Ni > Pb > Cr.