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Contaminations carried by effluents from communal waste dumps are a serious threat to underground waters. The effluents may contain solutes washed away by precipitation and also organic and mineral substances that arise during anaerobic and aerobic waste decomposition. Aside of substances that are known to be harmful to the human health (heavy metals), the effluents may contain a large number of common elements which are not regarded harmful at natural concentrations. In effluents from “young” dumps, where the waste undergoes acidic fermentation mainly, calcium concentration may exceed 3,000 mg⋅dm-3 and that of magnesium reach 1,500 mg⋅dm-3. Effluents from “old” dumps, where methane fermentation dominates, most often contain up to 400 mg⋅dm-3 of calcium and 200 mg⋅dm-3 magnesium. The aim of the work was to elucidtyate the character and dynamics of changes in concentration of the elements studied in effluents from a municipal waste dump at Maoelice near the city of Wrocław, and in underground waters of the adjacent land. Deposition of waste in this area began in the late 1960s. The ground conditions provide for an easy contact between underground water and dumped waste, and transport of the washed-out pollutants. Only part of the dump has sealing and drainage that conducts the effluents to a reservoir, where samples for this study were taken. At the turn of 1999 and 2000 the utilization of the dump was terminated and its reclamation began. Thus, the slopes of the refuse heap were fortified with reinforced ground, the cap sealed with synthetic-mineral material, and from the side of underground water inflow a shield was made (in 2002) that reached down to the impermeable ground layer in order to stop the inflowing waters. In 2004 the reservoir for effluents was filled in. The results, presented in this report, on the content of calcium and magnesium in underground waters flowing into the dump did not show any other extra contamination. In dump effluents the relations between calcium and magnesium concentration remained on similar levels. Like for other dumps, in the first years of study calcium concentration prevailed, whereas effluents from older dumps contained greater amounts of magnesium. Increased contents of calcium and magnesium in underground waters flowing under the unsealed part of the dump indicated at continuous inflow of contaminations, that were not eliminated by the technical means applied during reclamation of the installation. Variations in the properties of waters flowing out of the dump depended mainly on the composition of the inflowing waters (max. concentrations occurred concurrently) and the amount of contaminants emitted into the ground from the dump (relations between mean contents of calcium and magnesium varied in them like in the dump effluents).
The objective of the study was to determine the concentration of polycyclic aromatic hydrocarbons in soils in the immediate neighbourhood of illegal waste dumps and to determine the mutual relations among the particular PAHs as well as the relations between PAH and humus of a group of soils with natural and anthropogenically increased content of those compounds. Soil samples for the determinations were taken in the immediate neighbourhood of illegal dumping grounds of municipal wastes and materials that are predominantly construction materials. The collected soil material was used to determine the grain size composition of the soils, their reaction, content of organic matter and of polycyclic aromatic hydrocarbons with the method of high-efficiency liquid chromatography with fluorescence detection. The study revealed numerous instances of exceeding standard levels of individual PAHs as well as of their total content. Application of statistical analysis of concentrations permitted the division of the objects studied into two groups differing notably in the level of individual PAHs as well as in their total concentration. In the group of objects that were classified as non-contaminated, the existence of positive, statistically significant correlation was found between the total concentration of PAHs and the content of humus compounds, while in the group of contaminated objects the correlation was statistically non-significant.
The area around the Ilokun dumpsite, Ado-Ekiti was investigated with the aim of establishing the possible impact the contaminant plumes emanating from the dumpsite have on the subsurface aquifers. The Vertical Electrical Sounding (VES) field technique of the electrical resistivity method was adopted for the study, and the half-electrode spacing AB/2 varied from 1 to 65 m. A total of eight VES stations were occupied and a control VES point was located on the refuse dump. The VES data were interpreted quantitatively by partial curve matching and computer iteration, after which the geoelectric parameters were used to evolve a 2-Dimensional geoelectric section beneath the study area. The weathered layer beneath the control VES point was identified to be the aquifer unit, but the anomalously low resistivity of 18 ohm-m within the unit was interpreted as an evidence of pollution from conductive contaminant plume. The geoelectric section beneath VES 1 to 7 delineated four layers, these include the topsoil; the weathered layer; the fractured basement and the fresh basement. The resistivity and thickness range of the layers are 177 – 399 ohm-m and 0.7 – 1.2 m; 29 – 842 ohm-m and 1.0 – 3.4 m; 16 – 446 ohm-m and 4.5 – 45.5 m; and 289 – 2144 ohm-m respectively. The fractured layer constitutes the main aquifer unit beneath the seven VES points, but the anomalously low resistivity of 16 – 47 ohm-m within the fractured layer beneath VES 4, 5, 6 and 7 is suspected to be as a result of pollution from conductive contaminant plume emanating from the dumpsite. The fractured layer beneath VES 2 and 3 which does not show any evidence of pollution yet is at a risk of being contaminated, due to its interconnection with the polluted zone.
The paucity of standard engineered landfills in Nigeria has given rise to the proliferation of open waste dumpsites. The environment can be impacted by leachates from these dumpsites if not properly managed. This study assessed the characteristics of leachates from three open dumpsites in Warri Metropolis and its contamination potential using leachate pollution index (LPI). The dump sites had low pH with acidic level lower than the recommended limit. The calculated LPI values of the three sites ranges from 6.377 to 7.438. These values are low when compared to open dumpsites in other metropolitan areas of similar climatic conditions. The low value of LPI for leachate indicates relatively lower contaminant potential due to low concentrations of heavy metals, relatively young age of the landfill as well as low population and organic origin of the wastes. The calculated low LPI value does not in any way preclude the continuous monitoring of the dumpsites as the values recorded are just slightly below the threshold level. It is recommended that there should be an upgrade of all open dumpsites to a standard engineered landfill with a robust and effective monitoring put to curtail future release of deleterious materials from these dumpsites.
This paper presents results of physical chemistry research on solutes leached from mine waste dumps. Radioactivity research of that solutes is also included, taking into consideration its usage in earth constructions of hydraulic engineering. The research was done on samples taken from eight coal mine waste dumps. Impact on the water environment of that solutes was assessed, together with their radioactivity effect.
Electronic waste (e-waste) has become a subject of growing environmental concern in developing countries due to legal/illegal import of electronics from developed nations. In this study, concentrations of heavy metals in and around the largest e-waste dumping site in Nigeria, Alaba International Market in Lagos, was investigated. Concentrations of five heavy metals, namely: cadmium (Cd), chromium (Cr), lead (Pb), nickel (Ni), and zinc (Zn) in soil, water, and plant samples during the wet and dry seasons were measured using atomic absorption spectrometry (AAS). Samples were collected between October 2011 and May 2012 and digested using standard wet digestion methods. Pb recorded the highest values, while the lowest were found for Cd in all the samples during the dry season. Heavy metal concentrations were generally lower during the wet season due to increased aeration and dilution from rainfall. Results show that the total mean concentrations of the heavy metals decreased with depth in soil samples and distance from the dumpsite. Possible sources of contamination were also discussed. A noteworthy observation was that the concentrations of most of the heavy metals under investigation exceeded maximum permissible levels.
Secondary succession of mesostigmatid soil mites was studied in two types of reclaimed electric power plant waste dumps in Łaziska Górne (Upper Silesia, Poland) in 1997–1998. The dumps on which the studies were carried out differed in their construction and structure. We sampled 6 sites from 2 localities (Sites I–III and IV–VI), representing 3 stages of ecological succession. The sites differed floristically and in substrate physiochemistry i.e. organic carbon content (Corg) and total nitrogen (Nt). Site I representing pioneer stage was characterized by a poorly developed herb layer, a lack of trees and shrubs, and low Corg, Nt and humus content. Sites III, V and VI represented a pre-forest stage and were characterized by a larger number of plant species, higher percent cover of trees and shrubs, and high Corg, Nt and humus content. Sites II and IV represented an intermediate stages of succession. In 18 months, we took 540 samples of soil and litter, and we collected 4811 mites, assigned to 86 species of mesostigmatid mites. The mite communities differed between successional stages, mostly with respect to the relative dominance among species. At the pioneer stage of succession, the mite community was characterized by a “degraded” model of species abundance distribution, with a high dominance of Asca bicornis. At more advanced ecological stages (Sites III, V and VI), mite communities had similarities with communities of forest. Some of the most abundant species in Sites III, V and VI were typical forest inhabitants. Sites I–III represent a real succession of plant communities, soil development and mite communities, showing an increase in species richness of mites, diversity indices and of the number of dominant species (creative type of succession). The succession within Sites IV–VI reveals a different course (rise-and-fall).
Opisano metodę obróbki ścieków o wysokiej wartości ChZT oraz wysokiej zawartości chlorowcowanych węglowodorów, np. odcieki z wysypisk lub wody gruntowe o wysokiej zawartości wielopierścieniowych węglowodorów, które mogą być oczyszczane za pomocą samego ozonu lub kombinacji ozonu z UV, lub też w kombinacji oczyszczania biologicznego, ozonu i UV.
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