Assessment of non controlled land-fillings by geochemical and geophysical methods. Llobregat Delta (Barcelona, Spain).

The problems associated with municipal, abandoned or non-controlled landfills are of general concern, specially because of the interactions between the hazardous content of the leachates derived from them and groundwater. MacFarlane and others (1983) were the pioneers on this type of studies, later on, Cherry and others (1996) did more specific research on heavy metal thermodynamic with emphasis on providing data to assess or validate mathematical models at Borden landfill site (Canada). The main objective of this study was to characterise contaminated sites provoked by noncontrolled sand and gravel extraction quarries filled with urban, construction, industrial and chemical wastes. Using combined geochemical and geophysical data is possible to characterise contamination extension of the groundwater superficial aquifer and to deduce possible implications of water flux through landfillings.