The attention of local communities and authorities was focused on the level of nitrate concentration in ground-water of a wide coastal karstic aquifer, not far from the town of Bari (southern Italy), worried about the poten-tial effect of sanitary and unsecure landfills. Five landfills have operated from 1975, one after the other, using increasing safety and technological devices to reduce risks due to leachate leakages with consequent groundwater quality degradation. A multi-methodological approach was conducted to define the origin of nitrate contamination. The approach includes hydrogeological site characterization, chemical and isotopic study of groundwater and leachate, land use analysis and estimation of nitrogen contributions deriving from agricultural activities, focus-ing on the use of fertilizers and mineralogical study of groundwater suspended particles to define the origin of the iron and manganese in the water samples. In particular, the environmental isotopes of oxygen-18 (18O) and deuterium (2H) were used to investigate the origin of water in the aquifer system of the study area. The combination of NO3- concentration with ?15N-NO3- and 18O-NO3- in water also provides valuable information for identifying different sources of NO3- to the coastal aquifer. Groundwater and leachate samples were analyzed for 13C and Tritium (3H). Previous studies have demonstrated that the biogeochemical processes occurring within the landfill environment can produce a unique composition of these isotopes and therefore they can be utilized successfully to delineate the potential leachate influence.
Hydrogeological surveys to assess the groundwater nitrate contamination and the role of landfills (Apulia, Southern Italy)
Polemio M;Limoni PP;De Giorgio G;
2018
Abstract
The attention of local communities and authorities was focused on the level of nitrate concentration in ground-water of a wide coastal karstic aquifer, not far from the town of Bari (southern Italy), worried about the poten-tial effect of sanitary and unsecure landfills. Five landfills have operated from 1975, one after the other, using increasing safety and technological devices to reduce risks due to leachate leakages with consequent groundwater quality degradation. A multi-methodological approach was conducted to define the origin of nitrate contamination. The approach includes hydrogeological site characterization, chemical and isotopic study of groundwater and leachate, land use analysis and estimation of nitrogen contributions deriving from agricultural activities, focus-ing on the use of fertilizers and mineralogical study of groundwater suspended particles to define the origin of the iron and manganese in the water samples. In particular, the environmental isotopes of oxygen-18 (18O) and deuterium (2H) were used to investigate the origin of water in the aquifer system of the study area. The combination of NO3- concentration with ?15N-NO3- and 18O-NO3- in water also provides valuable information for identifying different sources of NO3- to the coastal aquifer. Groundwater and leachate samples were analyzed for 13C and Tritium (3H). Previous studies have demonstrated that the biogeochemical processes occurring within the landfill environment can produce a unique composition of these isotopes and therefore they can be utilized successfully to delineate the potential leachate influence.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
