Biostimulation proved to be the most efficient method in the comparison of in situ soil remediation treatments after a simulated oil spill accident

Abstract

The use of in situ techniques in soil remediation is still rare in Finland and most other European countries due to the uncertainty of the effectiveness of the techniques especially in cold regions and also due to their potential side effects on the environment. In this study, we compared the biostimulation, chemical oxidation, and natural attenuation treatments in natural conditions and pilot scale during a 16-month experiment. A real fuel spill accident was used as a model for experiment setup and soil contamination. We found that biostimulation significantly decreased the contaminant leachate into the water, including also the non-aqueous phase liquid (NAPL). The total NAPL leachate was 19 % lower in the biostimulation treatment that in the untreated soil and 34 % lower in the biostimulation than oxidation treatment. Soil bacterial growth and community changes were first observed due to the increased carbon content via oil amendment and later due to the enhanced nutrient content via biostimulation. Overall, the most effective treatment for fresh contaminated soil was biostimulation, which enhanced the biodegradation of easily available oil in the mobile phase and consequently reduced contaminant leakage through the soil. The chemical oxidation did not enhance soil cleanup and resulted in the mobilization of contaminants. Our results suggest that biostimulation can decrease or even prevent oil migration in recently contaminated areas and can thus be considered as a potentially safe in situ treatment also in groundwater areas.Electronic supplementary materialThe online version of this article (doi:10.1007/s11356-016-7606-0) contains supplementary material, which is available to authorized users.

Removal of Diesel Oil in Soil Microcosms and Implication for Geophysical Monitoring

“…For its removal, in situ bioremediation is considered an environmentally friendly and cost-effective solution, due to the metabolic capability of microorganisms to degrade the pollutants. So far, bioremediation is performed by means of • biostimulation: The addition of macro-and/or micronutrients to enhance indigenous biomass growth and pollutant degradation [1,2]; • bioaugmentation: The addition of enriched microbial cultures (autochthonous or allochthonous degraders) to the soil [3]; • combined biostimulation and bioaugmentation [4,5].…”

“…Several studies were carried out in different operative conditions, adopting one of the aforesaid strategies, and aimed to optimize hydrocarbon removal [3,[6][7][8][9]. It is widely known that biostimulation is an easier process to carry out [2,5,10,11]. However, when biostimulation does not give satisfactory results, bioaugmentation is adopted, or coupled methods are applied.…”

Effects of dissolved organic phase composition and salinity on the engineered sulfate application in a flow-through system

“…Hence, supplying sulfate as a remediation strategy to enhance the indigenous SRB community and biodegradation process has been proposed in the recent years Responsible editor: Bingcai Pan Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11356-020-07696-6) contains supplementary material, which is available to authorized users. (Kauppi et al 2011;Simpanen et al 2016;Müller et al 2017;Wei et al 2018).…”

Fenton’s reaction-based chemical oxidation in suboptimal conditions can lead to mobilization of oil hydrocarbons but also contribute to the total removal of volatile compounds

“…The growing demand for sustainable remediation techniques favours on-site and preferably in situ methods as a way to reduce carbon dioxide emissions from the treatment itself. Under favourable conditions, soil vapour extraction (SVE) of VOCs is an applicable and generally efficient treatment, and in Finland the one most commonly used in situ (Simpanen et al 2016; OISC 2017). However, since SVE is suitable only for VOCs, contamination from heavier, less volatile hydrocarbon fractions requires alternative treatment methods.…”