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The formation of biogas at municipal landfills and the significant emission of greenhouse gases from these facilities into the environment were the main reasons for analyzing the molecular composition of soil gas in the near-surface zone at the reclaimed part of the Barycz municipal waste landfill. The relations between the studied components (methane, carbon dioxide, light hydrocarbons and non-hydrocarbon components) and impact of the magnitude of recorded concentrations of methane and carbon dioxide on their emission to the atmosphere were evaluated. Two profiles were determined, along which 41 soil and landfill gas samples were taken at 20-meter intervals. At the same time, emissions were measured at each sampling point using a static chamber with a portable fluxometer. Chromatographic analysis showed that the concentrations of methane and carbon dioxide fluctuated in the ranges: 2.1 ppm – 76 vol% and 0.04 ppm – 11 vol%, respectively. Relatively high concentrations of these gases were determined at many of the measurement points, and this was particularly evident at the A-A’ profile, indicating stronger biochemical processes in this part of the landfill, or lateral migration of methane from the neighbouring stage II of the landfill, where biogas extraction is currently taking place. In addition, significant correlations between methane, carbon dioxide, and oxygen were demonstrated, indicating ongoing methane fermentation processes. Based on the study, it can be concluded that the southern part of the A-A’ profile is an optimal place to locate a degassing well from which biogas production could be used. However, the research is only preliminary and, it will be necessary to extend the soil gas tests before the final decision on the location of the well is made. Moreover, it has been shown that the concentrations of methane and carbon dioxide measured at points located outside the landfill were low. This means that generated biogas probably does not migrate beyond the boundaries of reclaimed waste landfill, but this will need to be confirmed by performing additional soil gas tests inside and outside the landfill area. The preliminary assessment of the effectiveness of the reclamation carried out was confirmed by the negligible values of the measured methane and carbon dioxide emissions on the surface. [ABSTRACT FROM AUTHOR]

The following research describes the influence of a metallurgical ash dump on both the soil environment and the atmosphere. Soil samples were collected along a line positioned on an unprotected, hazardous ash dump and extended into the adjacent, arable land. Three soil depths were sampled at 0–20-, 20–40- and 40–60-cm depth intervals, and in each sample, pseudo-total concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb, Ti, Zn, Li, Sr and V were analyzed. Additionally, emissions of CH4 and CO2 were measured at each sampling site. All emission measurements were taken in the same day, and the duration of gas measurements in each place was six minutes. The results demonstrate elevated concentrations of Cu, Cr, Pb and Zn on dump surface and along its margins, where the maximum concentrations of these elements are, respectively, 82, 23, 1144 and 8349 mg kg−1. Obtained results exceed several times both the natural background values and the values typical of local soils in the southern Poland. Moreover, natural background values for Fe, Mn, Ni, Li, Sr and V were exceeded, as well. Along the sampling line, no methane emission was detected, whereas the carbon dioxide flux varied from 7 to 42 g m−2 d−1. The reconnaissance study of the ash dump revealed a high contamination level of soils with heavy metals, which, together with the changes of soil environment, may cause migration of pollutants into the adjacent areas and, consequently, may generate hazard to the environment and, particularly, to the living organisms. Hence, further studies are necessary in order to evaluate the soil quality and the leaching of heavy metals from the dump. [ABSTRACT FROM AUTHOR]

Surface geochemical surveys were carried out in the Pawłosiów area in the eastern part of the Carpathian Foredeep. The research included an analysis of the molecular composition of soil gas samples as well as measurements of the calcite content, magnetic susceptibility and pH of soil samples. The results obtained were integrated with a geological-seismic model. Changes in the concentrations of total alkanes C 2 –C 5 in relation to changes in indirect geochemical indicators showed "compensatory" character. This means that in places where alkane concentrations were increasing, negative anomalies of magnetic susceptibility and a decrease in pH values were observed. It may be related to the intensity of the oxidation processes or reduction of the magnetic minerals in, as well as the reduced permeability of, the Miocene layers in the zones analysed. Moreover, the complex geochemical-geophysical interpretation showed a zone of anomalous values of the total C 2 –C 5 alkanes in the Pawłosiów area, which is suitable for prospecting. The research performed proved that a thorough analysis of the seismic record allowing subtle DHI anomalies appearing within the Miocene formations to be located, combined with the use of direct and indirect geochemical indicators, can help in identifying an area in terms of hydrocarbon potential. This applies in particular to this type of foreland basin, within which geological formations lie flat, and positive structures (anticlines) are hardly visible in seismic sections. In this type of structure, hydrocarbons can be accumulated in traps of a hybrid character (conventional and unconventional). The extensive zone of geochemical and geophysical anomalies found in the area of Pawłosiów may indicate the presence of this type of hydrocarbon accumulation. Comprehensive research, including direct and indirect geochemical methods in combination with a seismic survey, allows for a better assessment of the hydrocarbon potential of the studied area. • Direct and indirect surface geochemical indicators help interpret DHI seismic anomalies. • Alkane anomalies are associated with a decrease in magnetic susceptibility. • CH 4 and C 2 H 6 mainly migrate to the surface from shallow Miocene horizons, while C 3 H 8 and C 4 H 10 from deeper Miocene layers. • Integrated analysis of geochemical and geophysical indicators can help in the search for hybrid natural gas accumulations. [ABSTRACT FROM AUTHOR]