removed from the unsaturated zone. The hydraulic conductivity characterization of
the site was used to prove the hydraulic feasibility of this remediation. A combination of biostimulation and bioaugmentation within the closed bipolar system (one
extraction and two injection wells) was applied to enhance the in situ bioremediation. For biostimulation, nutrients were added and for stimulation of oxidation
processes, H 2 O 2 was injected into the aquifer. The injection of a zymogenous
consortium of isolated hydrocarbon-degrading microorganisms from the polluted
groundwater was used for bioaugmentation/reinoculation. The obtained average
extraction capacity in their study was 0.5 L/s, with an average injection capacity
of 0.25 L/s per well. By evaluating the changes in the content of total
chemoorganoheterotrophic and hydrocarbon-degrading microorganisms as well as
total hydrocarbon, the efficiency of the remediation method was measured. The
number of total chemoorganoheterotrophic and hydrocarbon-degrading microorganisms started to increase after bioaugmentation and biostimulation. Then the hydrocarbon concentration decreased in the groundwater from an initial 6.8 to 0.5 mg/L at
the end of the biotreatment. The used remediation method was very effective in
treating the contaminated groundwater.
Case 7: Southern Mediterranean
Bioremediation of Southern Mediterranean oil-polluted sites was investigated by
Daffonchio et al. (2013). The intense maritime traffic of oil tankers and high number
of oil extractive and refining sites through the basin coasts cause the Mediterranean
Sea to be at a very high risk of oil contamination. There are severe regulations
adapted by all Mediterranean countries to reduce the contamination resources and
great attention has been paid to biotreatment feasibility studies for the most critical
contaminated sites. Many studies have also discussed its serious polluted sites.
Analyses of the scientific studies indicates that the international research has
neglected the Southern Mediterranean side. Many researches in the Mediterranean
Sea were performed in contaminated sites of the Northern side of the basin.
Recently, the EU-funded research project ULIXES has been assigned to investigate
the bioremediation potential of the south of the Mediterranean Sea. The targets of
ULIXES are four main contaminated sites on the coastlines of Morocco, Jordan,
Tunisia, and Egypt including seashore sands, lagoons, and oil refinery contaminated
sediments. A cooperation of 12 Southern Mediterranean and European partners aims
to plug the present gap of information to develop novel bioremediation processes for
these contaminated sites with poor investigation. This study focuses on unraveling,
categorizing, cataloguing, exploiting, and managing the ecology and diversity of
microorganisms thriving in the contaminated sites. Isolation of new microorganisms
with the ability to degrade hydrocarbon and a series of state-of-the-art “meta-omics”
techniques are the baseline tools to extend our information on biodegradation ability
mediated by microorganisms under various environmental settings and to design the
new site-tailored bioremediation methods.
484
M. Fatehi et al.
the site was used to prove the hydraulic feasibility of this remediation. A combination of biostimulation and bioaugmentation within the closed bipolar system (one
extraction and two injection wells) was applied to enhance the in situ bioremediation. For biostimulation, nutrients were added and for stimulation of oxidation
processes, H 2 O 2 was injected into the aquifer. The injection of a zymogenous
consortium of isolated hydrocarbon-degrading microorganisms from the polluted
groundwater was used for bioaugmentation/reinoculation. The obtained average
extraction capacity in their study was 0.5 L/s, with an average injection capacity
of 0.25 L/s per well. By evaluating the changes in the content of total
chemoorganoheterotrophic and hydrocarbon-degrading microorganisms as well as
total hydrocarbon, the efficiency of the remediation method was measured. The
number of total chemoorganoheterotrophic and hydrocarbon-degrading microorganisms started to increase after bioaugmentation and biostimulation. Then the hydrocarbon concentration decreased in the groundwater from an initial 6.8 to 0.5 mg/L at
the end of the biotreatment. The used remediation method was very effective in
treating the contaminated groundwater.
Case 7: Southern Mediterranean
Bioremediation of Southern Mediterranean oil-polluted sites was investigated by
Daffonchio et al. (2013). The intense maritime traffic of oil tankers and high number
of oil extractive and refining sites through the basin coasts cause the Mediterranean
Sea to be at a very high risk of oil contamination. There are severe regulations
adapted by all Mediterranean countries to reduce the contamination resources and
great attention has been paid to biotreatment feasibility studies for the most critical
contaminated sites. Many studies have also discussed its serious polluted sites.
Analyses of the scientific studies indicates that the international research has
neglected the Southern Mediterranean side. Many researches in the Mediterranean
Sea were performed in contaminated sites of the Northern side of the basin.
Recently, the EU-funded research project ULIXES has been assigned to investigate
the bioremediation potential of the south of the Mediterranean Sea. The targets of
ULIXES are four main contaminated sites on the coastlines of Morocco, Jordan,
Tunisia, and Egypt including seashore sands, lagoons, and oil refinery contaminated
sediments. A cooperation of 12 Southern Mediterranean and European partners aims
to plug the present gap of information to develop novel bioremediation processes for
these contaminated sites with poor investigation. This study focuses on unraveling,
categorizing, cataloguing, exploiting, and managing the ecology and diversity of
microorganisms thriving in the contaminated sites. Isolation of new microorganisms
with the ability to degrade hydrocarbon and a series of state-of-the-art “meta-omics”
techniques are the baseline tools to extend our information on biodegradation ability
mediated by microorganisms under various environmental settings and to design the
new site-tailored bioremediation methods.
484
M. Fatehi et al.