## 4 Conclusions  
A feasibility study with different kinds of plants has evaluated the possible use of phytoremediation for agricultural soils contaminated by oil spills. Green technologies represent the best possible solution for remediation without damaging soil properties in these soils, whose quality is strictly related to the food chain and human health. The results show that phytoremediation can lower the concentration of hydrocarbons in the soil due to the ability to promote degrading microbial activity in the contaminated soil. The data also highlight the potential efficiency of selected PGPB to support and improve the biodegradation activity of the rhizospheric microbial population. Phytoremediation in agricultural areas offers the possibility to reduce contamination in an environmentally and economically sustainable way, also characterized by high social acceptability. The  
Figure 7: Concentration of pyrene in the soil (\(\upmu\)g kg\({}^{-1}\)d.m.) at initial conditions (Ss) and at the end of the mesocosm test for non-vegetated soils (Snv) and after the growth of \(Z\). _mays_ (Sv C) for different soils (A–D) during mesocosm tests. Data reported as the mean of replicates with the related standard deviation. results obtained in the study are strictly site-specific. However, the data strongly support the coordinated use of both plants and microorganisms to concretely use NBS as winning strategies to remediate recalcitrant organic compounds, such as petroleum hydrocarbons, maintaining or promoting soil quality. Indeed, an increase in the degradation was observed in vegetated soils with selected PGPB addition compared to natural attenuation soil phenomena, quantified in the up to around 30% removal of the C > 12 fractions, and the up to 70% removal of pyrene, considered an indicator of PAH contamination. Furthermore, the biomass produced after plant harvest can be exploited by waste-to-energy solutions, allowing greater benefit for the environment. Based on the results obtained, a field test preparatory to the full-scale reclamation is underway, in which, in addition to corn and sunflower, other local species (castor and sorghum) will be tested to gather more information and increase the chances of successful intervention. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app14020582/s1](https://www.mdpi.com/article/10.3390/app14020582/s1)]([https://www.mdpi.com/article/10.3390/app14020582/s1](https://www.mdpi.com/article/10.3390/app14020582/s1)), Figure S1: Spatial distribution of the sampling points, pipeline track and break-in point; Table S1: Concentration of the main hydrocarbon groups detected in the soil samples considered and the depth at which the samples were taken; Table S2: Fresh weight (g) of plants (shoots and roots) grown during microcosm tests; Table S3: Concentration of PAHs in the soils (ug kg\({}^{-1}\)) at initial conditions (Ss) and at the end of mesocosm test for non-vegetated soils (Snv) and after growth of _Z. mays_ (Sv). Conceptualization, M.V., E.F. and G.P. ; methodology, E.F., D.F., F.P., M.B. and G.P. ; software, M.V. ; validation, M.V. and E.F.; formal analysis, M.V. and A.P.R. ; investigation, D.F., F.P. ; M.B. ; resources, E.F. and G.P. ; data curation, M.V. ; writing--original draft preparation, M.V., E.F., G.P. and A.P.R. ; writing--review and editing, M.V. ; visualization, M.V. ; supervision, M.V. ; project administration, E.F.; funding acquisition, G.P. All authors have read and agreed to the published version of the manuscript. This research was supported by Eni S.p.A, Research & Technological Innovation Department, San Donato Milanese (Italy) and fully funded by Syndial S.p.A. (now Eni Rewind S.p.A.), agreement number 3500047416. Not applicable. Data availability Statement: Data are contained within the present article. The authors thank [PERSON], IRET-CNR, for her technical assistance in phytoremediation experiments. [PERSON] and [PERSON] are employees of Eni S.p.A.