Fingerprinting hydrocarbons in a contaminated soil from an Italian natural reserve and assessment of the performance of a low-impact bioremediation approach

An environmentally friendly proceduresuitable to restore a protected area was evaluated atlaboratory scale. Soil contaminated by high molecularweight (C>10) aliphatic hydrocarbons and by chromiumwas withdrawn from the study site and a qualitativestudy of soil hydrocarbon components was first performedin order to assess the potential source ofcontamination. To this aim, a number of characteristicdiagnostic ratios of hydrocarbon components werederived by processing chromatographic data, and wereused as indicators for distinguishing anthropogenic fromnatural hydrocarbons. Then, the efficiency of landfarmingfor soil remediation was tested by comparingthe effect of a few selected amendments and by monitoring the fate of chromium. Soil microbialabundance and activity were also evaluated. Resultsshowed that soil hydrocarbons were mainly of anthropogenicorigin and land treatment allowed effectivedegradation by native microbial populations even in theabsence of amendments. The investigated procedureshad no effect on the mobilisation of chromium thatremained in its stable form of Cr(III). Conventional landtreatment may therefore be an effective and safeprocedure for the removal of hydrocarbons even in thepresence of chromium, and may be applied to areaswhere low-impact procedures are strictly required.