RESEARCH ARTICLE Detection of the natural origin hydrocarbon contamination in carbonate aquifers (central Apennine, Italy) Sergio Rusi 1 & Diego Di Curzio 1 & William Palmucci 1 & Riccardo Petaccia 1 Received: 23 October 2017 / Accepted: 13 March 2018 # Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract The water–rock interaction is discussed in this study for some Central Apennine aquifers and their relative springs, where the geological and hydrogeological setting is potentially responsible for hydrocarbon contamination. The contamination is related to the presence of limestone formations with high organic content that are connected to the genesis of hydrocarbons in the Central- Southern Apennines. Thanks to a multidisciplinary approach based on a seasonal monitoring of hydrogeological, hydrogeo- chemical, organic chemical, and isotopic variables, and to a detailed geological analysis, it was possible to demonstrate that the bituminous schists within the bituminous dolomite formation (a Triassic Formation presents in the Gran Sasso acquifer), the bituminous intercalations within the Bolognano Formation (an Olocenic calcareous Formation in the Majella acquifer), and the petroleum-saturated rocks of the Bolognano Formation (in the Morrone acquifer) are all able to leach hydrocarbons into groundwater. The results suggest that more detailed studies are required for areas where lithologies with fossil organic compo- nents are present. Insights should further investigate the interaction between groundwater and rocks in terms of organic com- pounds as well as inorganic compounds. In particular, the study also suggests that the supplementary quantification of hydro- carbon compounds in bituminous rock and the leaching tests are analyses that provide reliable results. From the normative point of view, the results of the study can be useful when dealing with hydrocarbon contamination resulting from anthropogenic activities within catchments where formations with high concentration of organic matter are present. In these cases, it will possible to assess the natural background concentrations and review the threshold values upwards. Keywords Natural contamination . Hydrocarbons . Bituminous formations . Petroleum springs . Groundwater . Central Apennines Introduction In the last decades, the increasing environmental pressure on groundwater resources, due to the impact of the growing hu- man activities, led the European Commission to implement water policies such as 2000/60/EC and 2006/118/EC (European Commission 2000, 2006). These environmental actions, aimed to prevent and limit the input of pollutants into groundwater and to preserve their quality, require the Member States to define threshold values (TVs) about pollutant concentration in the aquifers. Italy transposed the European Directives into the National Decree 152/2006 (Italian Republic, 2006) and National Decree 30/2009 (Italian Republic, 2009) and subsequent amendments and additions, setting TVs at the national level on the basis of chemical, bio- logical, and health parameters. At the local scale, derogation to these TVs is permitted where the natural hydrogeological prop- erties are such that some ions have anomalous concentrations. Many of these anomalous concentrations are dependent on the interaction of the groundwater with the aquifer matrix and on the water–rock interaction time. Defining the hydrogeochemi- cal properties of the aquifer that govern the groundwater–aqui- fer matrix interaction, normally undertaken in terms of mineralogy and petrography, is of fundamental importance. The presence of limestone high organic content formations (HOCFs), which are connected to the genesis of hydrocarbons in the Central-Southern Apennines, suggests that it is neces- sary to assess these organic substances when investigating the Responsible editor: Philippe Garrigues * Sergio Rusi sergio.rusi@unich.it 1 Engineering and Geology Department, University BG. d’Annunzio^ Chieti-Pescara, Pescara, Italy Environmental Science and Pollution Research https://doi.org/10.1007/s11356-018-1769-9