scale; (4) Density effects, which were not encountered at the column scale, caused
problems for oxidant injection in the tanks; (5) Removal techniques that are equal for
mass-based removal goal were quite different in lowering the dissolved contaminant
flux from the system. Therefore, the ranking of techniques based on mass removal
may not be appropriate and be replaced by a flux reduction selection; and (6) A need
to perform experiments at three experimental scales is evidenced: batch studies allow
sufficient variations in experimental conditions, the column experiments permitted
the optimization of surfactant and oxidant injection, whereas tank experiments allow
studies under heterogeneous flow conditions.
Keywords In situ remediation · Contaminant removal · Groundwater · Upscaling ·
Fuels
4.1 Introduction
Soil and groundwater pollution with hydrocarbons is recognized as a worldwide
problem and a health danger due to degraded drinking water quality and vapor
intrusion into buildings. Diesel fuel is commonly used in cars, trucks, and trains.
This widespread use can lead to spills into soils and sometime in groundwater.
Diesel fuel is composed of about 40% n-alkanes, 40% of iso- and cycloalkanes and
about 20% of aromatic hydrocarbons (Chia-Hsien et al. 2011). Among these compounds, aromatic hydrocarbons are the most soluble and thus present a significant
risk to water bodies, even with a low molar fraction into the oil phase. At contaminated sites, the leakage results in the presence of a Light Non-Aqueous Phase Liquid
(LNAPL) lenses lying above the water table. The first treatment action is often to
pump the oil phase when it is thick enough. However, at the end of this treatment
period there is always a residual phase, with NAPL saturation that is often around
20 and 30% but can reach 50% in the saturated zone (Pennell et al. 1993). In most
cases, the residual amount of diesel present in the pores lead to a significant
remaining risk at the target.
Hundreds of research papers have addressed the remediation of sites contaminated by these hydrocarbons. Among the most common techniques, one can cite
Sparging and In Situ Chemical Oxidation (ISCO). Surfactant injection and thermal
treatment have recently more and more implemented (Kuppusamy et al. 2016;
McGuire et al. 2006). Biodegradation of dissolved compounds also occurs and can
be enhanced by injecting different products, notably when plume remediation is
considered (Stroo et al. 2012). This chapter focuses on techniques that lead to a
relatively rapid treatment of residual source zones and thus dedicated to sparging,
ISCO, surfactant, and thermal treatments.
Numerous factors influence the efficiency of the treatment. Some of them, like the
overall reaction rates or reaction types can be investigated through Batch studies.
Batch experiments are usually slurries of liquids and solids. This is different from in
situ conditions in a (static) porous medium. In order to get closer to field conditions,
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F. Jousse et al.
problems for oxidant injection in the tanks; (5) Removal techniques that are equal for
mass-based removal goal were quite different in lowering the dissolved contaminant
flux from the system. Therefore, the ranking of techniques based on mass removal
may not be appropriate and be replaced by a flux reduction selection; and (6) A need
to perform experiments at three experimental scales is evidenced: batch studies allow
sufficient variations in experimental conditions, the column experiments permitted
the optimization of surfactant and oxidant injection, whereas tank experiments allow
studies under heterogeneous flow conditions.
Keywords In situ remediation · Contaminant removal · Groundwater · Upscaling ·
Fuels
4.1 Introduction
Soil and groundwater pollution with hydrocarbons is recognized as a worldwide
problem and a health danger due to degraded drinking water quality and vapor
intrusion into buildings. Diesel fuel is commonly used in cars, trucks, and trains.
This widespread use can lead to spills into soils and sometime in groundwater.
Diesel fuel is composed of about 40% n-alkanes, 40% of iso- and cycloalkanes and
about 20% of aromatic hydrocarbons (Chia-Hsien et al. 2011). Among these compounds, aromatic hydrocarbons are the most soluble and thus present a significant
risk to water bodies, even with a low molar fraction into the oil phase. At contaminated sites, the leakage results in the presence of a Light Non-Aqueous Phase Liquid
(LNAPL) lenses lying above the water table. The first treatment action is often to
pump the oil phase when it is thick enough. However, at the end of this treatment
period there is always a residual phase, with NAPL saturation that is often around
20 and 30% but can reach 50% in the saturated zone (Pennell et al. 1993). In most
cases, the residual amount of diesel present in the pores lead to a significant
remaining risk at the target.
Hundreds of research papers have addressed the remediation of sites contaminated by these hydrocarbons. Among the most common techniques, one can cite
Sparging and In Situ Chemical Oxidation (ISCO). Surfactant injection and thermal
treatment have recently more and more implemented (Kuppusamy et al. 2016;
McGuire et al. 2006). Biodegradation of dissolved compounds also occurs and can
be enhanced by injecting different products, notably when plume remediation is
considered (Stroo et al. 2012). This chapter focuses on techniques that lead to a
relatively rapid treatment of residual source zones and thus dedicated to sparging,
ISCO, surfactant, and thermal treatments.
Numerous factors influence the efficiency of the treatment. Some of them, like the
overall reaction rates or reaction types can be investigated through Batch studies.
Batch experiments are usually slurries of liquids and solids. This is different from in
situ conditions in a (static) porous medium. In order to get closer to field conditions,
212
F. Jousse et al.