The RESPONSE project aims at improving the use of coupled reactive transport models to simulate the fate of inorganic and organic contaminants within environments, characterised by a fluctuating shallow groundwater table – inducing strong hydraulic, physico-chemical and redox gradients. Three case studies were selected based on the presence of inorganic and/or organic contamination. Two sites are cemeteries where groundwater pollution by herbicides (2,6-dichlorobenzamide (BAM) – a persistent metabolite of herbicide dichlobenil) was detected. Top soil and groundwater samples were collected and the BAM degradation and mineralization potential of soil microbiota is tested in the laboratory. It is hypothesized that BAM degradation is strongly affected by DOC quality (measured through specific UV absorbance) and quantity. RESPONSE will investigate whether predictions of dichlobenil and BAM migration in soils and groundwater can be improved by taking into account DOC quality/quantity.The third site is a former municipal landfill, where redox zonation and contamination by As is observed. This site is primarily used to study the level of hydrogeological and geochemical detail needed to predict the migration of pollutants in a satisfactory way. This hypothesis is tested by comparing predictions using site specific measured parameters (soil and subsoil hydraulic parameters, in-situ groundwater flow characterization, etc.) with predictions using parameters inferred from existing hydrological/ geochemical data available in data bases. Moreover, an integrated tool is developed to simulate water flow and reactive solute transport in the subsurface focusing on the water table interface. This is achieved by loosely coupling the existing HYDRUS, MODFLOW, MT3D-USGS and PHREEQC codes at the lowest level and adding functionalities for the transfer of solute concentrations. The HYDRUS package for MODFLOW (Seo et al., 2007) has been updated and PHREEQC functionalities are coupled to both the unsaturated zone (based on HPx software; Jacques et al., 2018) and the saturated zone.
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RBINS Staff Publications 2019
Numerous fossil remains (vertebrates, molluscs and plants) were found in more than twenty sites of the Süttő Travertine Complex during the last 150 years. The majority of these remains were recovered from fissures of the travertine, but also from the travertine and an overlying loess–paleosol sequence. The aims of this study were to review the fossil content, to determine the stratigraphical positions of the various vertebrate faunas of Süttő and provide paleoecological interpretation of the periods on the basis of their faunas and floras. In addition, this paper describes new faunas and floras from the sites Süttő 16–20 and provides 14C dates for Süttő 16. On the basis of the new uranium series isotope and optical dating (OSL), the age of the travertine complex is Middle Pleistocene (235 ± 21–314 ± 45 ka, \MIS\ 7–9), while the age of the loess–paleosol sequence in superposition of the travertine is Middle–Late Pleistocene (MIS 2–MIS 6). In contrast, the fossils of the travertine indicated an older, Pliocene–Early Pleistocene age. A fissure (Süttő 17) and a red clay layer (Süttő 19) contained mammal faunas of Early–Middle Pleistocene age. These results indicated the existence of older travertine in certain quarries (Hegyháti quarry, Cukor quarry). Sedimentological and \OSL\ data of well-dated layers of the loess–paleosol sequence (Süttő/LPS) at Süttő allowed a correlation with the layers of Süttő 6. The paleosol layer in the upper part of the sequence of Süttő 6, was correlated with a pedocomplex of the overlying loess–paleosol sequence, which was dated to \MIS\ 5c (upper, dark soil) and \MIS\ 5e (lower, reddish brown soil). The paleoecological analysis of the mammal and mollusc faunas supported the former interpretation of Novothny et al. (2011) inferring warm, dry climate during the sedimentation of the upper layers, and more humid climate for the lower layers). However, the fauna of the lower soil layer indicated cold climate, so an age of \MIS\ 5d is suggested. Dating of the fissure faunas is based on similarity studies. For some faunas, this method cannot be used, because of the low number of species. On the basis of the species compositions and former interpretations, these faunas originated mainly from sediments that were deposited under cold climatic conditions. Other fissure faunas were dated by \AMS\ 14C (Süttő 16), or by correlation with soil layers of Süttő 6. According to these results, most of the fissure faunas can be correlated with different phases of \MIS\ 5. However, there are a younger (MIS 2) and an older (Early–Middle Pleistocene) fissure fauna also.
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