Abstract
An environmental baseline study has been conducted in a large (370 km2) natural and remote area of Southern Italy on behalf of an International Oil Company (IOC) to verify the potential impact of exploration and production activities. The territory is mainly mountainous and covered by forests, with limited human pressures and significant biodiversity.
The study has been undertaken over a period of approximately one year. Four seasonal field campaigns have been conducted, to investigate the chemical quality of soil, waters (springs, rivers and groundwater), air and the ecological and functional quality of the river environments, with the definition of EBI (Extended Biotic Index), WSI (Wild State Index) and BSI (Buffer Strip Index). The study comprised a complex data analysis, with the use of statistical, hydrochemical and geochemical methods.
Chemical analyses showed an unexpected presence of heavy metals in all the environmental matrices. Statistical and geochemical methods have been applied to evaluate this result. Principal Components Analysis (PCA) has been used to simplify and aggregate the original information with a repeatable and defensible method. Geochemical interpretation of soil sample test results was undertaken to investigate correlation of heavy metal concentrations with parameters unlikely to have been affected by human activities, such as Iron and Aluminum concentrations which are widely diffused in natural soils, and with silt and clay abundance. Undisturbed bedrock samples have also been collected and analyzed, to make a comparison with the concentrations found in soil samples. The statistical and geochemical methods applied helped to interpret the natural background abundance of heavy metals.
The aim of the project was to establish an environmental baseline for due diligence purposes in a exploration site and to demonstrate that the unexpected heavy metals concentrations measured in soil and water probably have a natural origin. The application of such methods can be of general interest at exploration and production sites to define the environmental baseline prior to the beginning of the development activities.
