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EN
Groundwater vulnerability assessment is an important environment management tool. In this study assessment of groundwater vulnerability to pollution was conducted by DRASTIC method in urban area, represented by the Bielany - district of Warsaw. The results of this study showed that 70% of the study area has medium or moderately high pollution potential and nearly 30% area has low and very low pollution potential. Two sensitivity tests were performed: the map removal sensitivity analysis and the single-parameter sensitivity analysis. Sensitivity analysis is defined as the evaluation of the effect of changes of input values on the output of the model, therefore, in order to reduce subjectivity of groundwater vulnerability assessment sensitivity analysis was performed for DRASTIC procedure. Both tests highlighted the role of the parameter „depth to water" in groundwater vulnerability assessment.
EN
The purpose of this paper was to analyze the effect of detailed recognition and correct mapping of the boundaries between layers of different grain sizes on the results of modelling tests of the vadose zone. The modelling was performed using UnSat Suite software that enables modelling of water permeability and migration ofpollutants through the vadose zone using various numerical programs, including VS2DT that was used in this case study. Directfield research, including drilling of boreholes and ground-penetrating radar investigation, has shown a significant variation in lithology of the vadose zone in a small test area located in Włocławek city. Various sand fractions have been found: from fine to coarse sand, with varying filtration parameters and moisture content. Ground-penetrating radar investigations have enabled a more accurate recognition and refinement ofgeologic structures, particularly in the context oflithological boundaries, including the space between boreholes. The results of the modelling tests conducted in the vadose zone enabled determination of the velocity, time and volume of infiltration water.
PL
Celem badań było określenie zmian współczynnika filtracji popiołu lotnego w wyniku dodania bentonitu w ilości 2, 5 i 10%. Ponieważ popiół lotny, z uwagi na swoją budowę wewnętrzną może stanowić materiał uszczelniający, a jednocześnie jego pozyskanie nie wiąże się z dużymi kosztami, Autorzy rozważyli możliwość połączenia go z niewielkim dodatkiem bentonitu, w celu wytworzenia stosunkowo niedrogiego materiału uszczelniającego. W ramach badań przedmiotowych wykonano oznaczenia współczynnika filtracji przy zmiennym gradiencie hydraulicznym za pomocą edometru, na próbkach preparowanych w warunkach laboratoryjnych przy wskaźniku zagęszczenia 0,95. W wyniku przeprowadzonych badań zauważono, iż nawet niewielki (2%) dodatek bentonitu powoduje zmniejszenie współczynnika filtracji o jeden rząd wielkości w stosunku do wyjściowego. Przy 10% dodatku obserwuje się zmniejszenie wspomnianego parametru o dwa rzędy wielkości. Patrząc z punktu widzenia „klasyfikacji charakterystyki przepływu” i „klasyfikacji przepuszczalności”, można stwierdzić, iż czysty popiół posiada słabą charakterystykę przepływu i niską przepuszczalność; 2% dodatek bentonitu powoduje iż badana mieszanka ma bardzo niską przepuszczalność, natomiast 10% dodatek bentonitu czyni ten materiał praktycznie nieprzepuszczalnym.
EN
The aim of the tests was to determine the changes in the permeability coefficient of fly ash by adding 2, 5 and 10% of bentonite. Due to its internal structure, fly ash, can be serve as a sealing material. Simultaneously, its acquisition does not involve high costs. Therefore, the authors considered the possibility of combining it with a small addition of bentonite to produce a relatively inexpensive sealing material. During the tests, the permeability coefficient was marked using an oedometer with a variable hydraulic gradient on laboratory prepared tests samples at compaction index 0.95. As a result of carried out tests it was noted that even a small (2%) bentonite addition caused the reduction of a permeability coefficient by one order of magnitude, relative to starting value. At the addition of 10%, a reduction by two orders of magnitude of the afore-mentioned parameter was noted. From the point of view of “characteristic flow water” and “classification of permeability”, it can be concluded that the pure ash exhibits weak flow water characteristic and low permeability; the 2% addition of bentonite lowers the permeability of mixtures even further, while the addition of 10% renders this material virtually impermeable from the practical point of view.
EN
The marsh zone areas include about 2,440 km2 in Kampinos National Park, which amount nearly 30% of park and its buffer’s surface. The specific characteristic of the KNP marsh zones is presence of shallow groundwater; mean depth to groundwater table is formed from 0.16 do 2.30 m. Range and tendencies of groundwater level changes in marsh zones are related to the influence of geogenic and anthropogenic factors. Among geogenic factors, the most important sense have distribution and seasonality of precipitation, which determine the value of infiltration recharge, evapotranspiration and watercourse drainage of shallow groundwater system. The basis of the researches on defining the role of factors determining range and tendencies of groundwater level changes in KNP, has been regular monitoring observations conducted in the park since 1999. The results of correlation indicate on high diversification of relation: atmospheric precipitation – depth to groundwater level. Determination of trend on the different significance levels provides detaching areas where relation between groundwater levels and precipitation is so high that influence of other environmental factors indicating on depth to groundwater table could be skipped and areas where the relation is so low, which indicates on influence of various factors. Groundwater level in marsh areas are characterized by large dynamic of changes. Since 1999, the beginning of the observations, downward trend of groundwater table has been observed, after 2003 the character of trend has been conversed. Another decreasing trend has started in 2007 and with assumption of previous tendencies, its inversion will occur after 2011 (after extremely dry year). Geostatistical analysis of spatial difference of mean year amplitude of depth to groundwater level enabled the assessment of surface water influence on groundwater level changes. The areas of highest value of amplitudes are localized in southern part of northern marsh belt and central part of southern marsh belt. Anthropogenic factors such as: water withdrawal and improper draining system, have not changed in recent years, so their influence can be called as “steady” and acceptably to eliminate in case of elaborating of programs of wetland areas renaturalisation.
PL
Mapy podatności naturalnej wód podziemnych na zanieczyszczenia stanowią wizualizację oceny podatności wód podziemnych na zanieczyszczenia. Są one jednym z najważniejszych elementów uwzględnianych przy podejmowaniu decyzji odnośnie zagospodarowania terenu i obiektów potencjalnie uciążliwych dla środowiska. Badania podatności wód podziemnych na zanieczyszczenia zostały przeprowadzone na obszarze Kampinoskiego Parku Narodowego (skala regionalna) oraz na wytypowanym poligonie w pobliżu Wiktorowa w Kampinoskim Parku Narodowym (około 30 km2) w skali lokalnej. Ocenę podatności naturalnej przeprowadzono przy zastosowaniu zmodyfikowanej metody DRASTIC oraz na podstawie szacunku czasu przesączania się zanieczyszczeń konserwatywnych. Uzyskane rezultaty wskazują, że rezultat oceny zależy od wykorzystanej metody, stopnia rozpoznania warunków hydrogeologicznych, zastosowanych uproszczeń oraz wyznaczonego celu badań.
EN
Maps of natural groundwater vulnerability to contamination illustrate the assessment of natural groundwater vulnerability. They are also one of the important components that are taken into consideration while making a decision as regards the site management and objects potentially troublesome for the environment. The researches of natural vulnerability were conducted for the area of the Kampinoski National Park (on a regional scale) and for the area (about 30 km2) near Wiktorów (part of the Kampinos National Park) on a local scale. The assessment of vulnerability has been performed with the use of the modified DRASTIC method and calculations of the time migration method of a contaminant through the unsaturated zone. The results of the study indicate that the evaluation of natural groundwater vulnerability to contamination depends on the following factors: research methodology, degree of area recognition, applied simplifications and the purpose of research.
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