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EN
The presented studies focus on changes in groundwater levels and chemistry, and the identification of important factors influencing these changes on short- and long-term scales in urban areas. The results may be useful for rational and sustainable groundwater planning and management in cities. The studies concerned three aquifers: (1) the shallow Quaternary aquifer, (2) the deep Quaternary aquifer, and (3) the Oligocene aquifer in the capital city of Warsaw (Poland). The spatial variability of groundwater recharge was determined and its changes in time were characterized. The characteristics of groundwater levels were based on long-term monitoring series. The results indicate that urban development has caused overall reduction in infiltration recharge (from 54 to 51 mm/year), which is particularly clear in the city suburbs and in its centre, where land development has significantly densified during the last 30 years. Studies of groundwater levels indicate variable long-term trends. However, for the shallowest aquifer, the trends indicate a gradual decrease of the groundwater levels. In the case of the much deeper Oligocene aquifer, groundwater table rise is observed since the 1970s (averagely c. 20 m), which is related with excessive pumping. Based on the studied results, the groundwater chemistry in the subsurface aquifer indicates strong anthropogenic influence, which is reflected in multi-ionic hydrogeochemical types and the occurrence of chemical tracers typical of human activity. The Oligocene aquifer is characterized by a chemical composition indicating the influence of geogenic factors.
EN
The aim of the study was to propose a range of interpretation of the results of qualitative groundwater monitoring by using geochemical indicators to assess the degree of anthropogenic groundwater pollution. The location, scope and frequency of groundwater testing dedicated to the possibility of indicating the degree of pressure resulting from the activity in the field of hydrocarbon exploration and exploitation is proposed. On the basis of multistage monitoring research in the area of hydrocarbon exploration and exploitation, the qualitative groundwater base state was determined and change trends were characterized at each subsequent testing stage. Anthropogenic transformations of groundwater chemistry are the result of many overlapping factors, which is why the reason of water quality change is difficult to identify. The very statement of the presence of high values of physico-chemical parameters in waters does not have to prove the influence of the monitored object on their composition. It is proposed to use geochemical indicators: enrichment factor, pollution factor, geoaccumulation factor, and pollution load indicator to assess the degree of anthropogenic pollution of groundwater in the area of hydrocarbon exploration and exploitation. The geochemical indicators, which are proposed for use, enable the identification of substances of anthropogenic origin in waters and the detection of even the initial degree of anthropopressure on their composition in specific mining activities.
EN
Approximately 80% of water extracted from oil and gas deposits in Poland is disposed of by injection into the rock matrix. The aim of the model research was to predict both the hydrochemical reactions of water injected into wells for its disposal and the hydrogeochemical processes in the reservoir formation. The purpose of hydrogeochemical modeling of the hydrocarbon formation was also to determine the potential of formation waters, injection waters, and their mixtures to precipitate and form mineral sediments, and to determine the corrosion risk to the well. In order to evaluate saturation indices and corrosion ratios, the geochemical programs PHREEQC and DownHole SAT were used. The results of hydrogeochemical modeling indicate the possible occurrence of clogging in the well and the near-well zone caused mainly by the precipitation of iron compounds (iron hydroxide Fe(OH)3 and siderite FeCO3) from the formation water due to the presence of high pressures and temperatures (HPHT). There is also a high certainty of the precipitation of carbonate sediments (calcite CaCO3, strontianite SrCO3, magnesite MgCO3, siderite FeCO3) from the injection water within the whole range of tested pressures and temperatures. The model simulations show that temperature increase has a much greater impact on the potential for precipitation of mineral phases than pressure increase.
EN
Biocomposite foam scaffolds of poly(ε-caprolactone) (PCL) with different porogenes were producedwith batch foaming technique using supercritical carbon dioxide (scCO2)as a blowing agent. Inperformed experiments composites were prepared from graphene-oxide (nGO), nano-hydroxyapatite(nHA) and nano-cellulose (nC), with various concentrations. The objective of the study was to explorethe effects of porogen concentration and foaming process parameters on the morphology and me-chanical properties of three-dimensional porous structures that can be used as temporary scaffolds intissue engineering. The structures were manufactured using scCO2as a blowing agent, at two variousfoaming pressures (9 MPa and 18 MPa), at three different temperatures (323 K, 343 K and 373 K) fordifferent saturation times (0.5 h, 1 h and 4 h). In order to examine the utility of porogenes, a number oftests, such as static compression tests, thermal analysis and scanning electron microscopy, have beenperformed. Analysis of experimental results showed that the investigated materials demonstrated highmechanical strength and a wide range of pore sizes. The obtained results suggest that PCL porousstructures are useful as biodegradable and biocompatible scaffolds for tissue engineering.
PL
Badania podatności wód podziemnych przeprowadzono w dolinie Wisły, na obszarze płytkiego występowania wód podziemnych. Wykonano analizę zmian stanów wód podziemnych w celu identyfikacji wartości średnich oraz wartości najniższych w wieloleciu 1999–2013. Na modelu hydrodynamicznym określono wartości zasilania infiltracyjnego odpowiadające stanom średnim w wieloleciu oraz stanom najniższym w warunkach suszy hydrogeologicznej. Przeprowadzono wariantową ocenę podatności wód podziemnych na zanieczyszczenia przy zastosowaniu metody DRASTIC, przyjmując do obliczeń średnie i najniższe stany wód podziemnych i odpowiadające im wartości zasilania infiltracyjnego. Mapy podatności dla obu wariantów podatności: podatności średniej (A) oraz w warunkach suszy hydrogeologicznej (B), przedstawiają zróżnicowanie przestrzenne występowania poszczególnych klas podatności. W wariancie A największą powierzchnię zajmuje średniowysoka i średnia klasa podatności. W okresie suszy hydrogeologicznej największą powierzchnię zajmuje średnia klasa podatności. Wyniki badań potwierdzają potrzebę wariantowej oceny podatności, szczególnie w płytkich systemach hydrogeologicznych, w których objęte są ochroną zróżnicowane ekosystemy, w tym ekosystemy zależne od wód podziemnych.
EN
The study of groundwater vulnerability was carried out in the Vistula river valley, in the area of shallow groundwater occurrence. An analysis of groundwater level changes was preformed to identify average values and the lowest values in the period of 1999–2013. On the hydrodynamic model, infiltration rate was determined corresponding to average groundwater levels and the lowest levels representing hydrogeological drought. A variant evaluation of groundwater vulnerability to pollutions was done using the DRASTIC method, assuming the average and the lowest groundwater levels and the corresponding infiltration rates for the calculation. The vulnerability maps for both vulnerability options: medium (A) and hydrogeological drought conditions (B), show the spatial diversity of individual vulnerability classes. In Variant A, the medium and medium high classes occupy the largest area. During the hydrogeological drought the medium class is the largest area. The research results support the need for a variant susceptibility assessment, especially in shallow hydrogeological systems in which diverse ecosystems are protected, including groundwater-dependent ecosystems.
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