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Mercury (Hg) cannot be destroyed therefore only two principal processes are available for the tre... more Mercury (Hg) cannot be destroyed therefore only two principal processes are available for the treatment of Hg-contaminated soil: 1) separation of Hg from soil (through wet-sieving and/or chemical e ...
Biogeochemistry, Jan 23, 2008
<p>&#160;Per- and polyfluoroalkyl substances (PFAS) are fluorinated organic... more <p>&#160;Per- and polyfluoroalkyl substances (PFAS) are fluorinated organic chemicals that have extensively been used for more than five decades worldwide, resulting in their ubiquitous spreading . In the light of their toxicity, recalcitrance and bioaccumulation potential, their use and disposal are increasingly being limited. Groundwater is one of the environmental pathways critical for PFAS dispersal and subsequent human exposure. Case studies on PFAS groundwater contamination are lacking and remediation efforts applied in full-scale are limited. In this context, the main objective of this study was to quantify the extent of PFAS contamination in the subsurface and evaluate the effectiveness of a trap-and-treat <em>in-situ</em> soil remediation method with the use of colloidal activated carbon. A PFAS-contaminated site was selected for investigation in Sweden, that has previously been used for fire-fighting training with PFAS-containing aqueous fire-fighting foam (AFFF).</p><p><strong>&#160;</strong>PFAS concentrations and hydrological properties of the contaminated site were investigated. Groundwater was sampled through five monitoring wells, while surface water samples were collected at four different locations in a stream adjacent to the site monthly-bimonthly. PFAS concentrations were quantified for 11 individual PFASs. Colloidal activated carbon was injected in the subsurface, aiming for a good distribution of the sorbents in the treatment zone. Monitoring wells were drilled upstream and downstream to the injection well, identifying variations in concentrations through time. Total oxidizable precursor concentrations were also quantified in two observation wells. Other parameters that were monitored in the wells included pH, conductivity and metals concentrations. Groundwater levels were measured by manual sounding as well as by automated logging with barometric compensation. Aquifer characteristics were defined by slug tests and the site&#8217;s geological characteristics were investigated.</p><p>Prior treatment, groundwater concentrations of &#8721;PFASs were up to 24 &#956;g L<sup>-1</sup>, while two significant hotspots were identified. &#8721;PFASs concentrations decreased by ~74% based on the original concentration within and directly downstream of the treatment zone approximately three months after applying the colloidal activated carbon. Differences in the PFAS composition profile after injection, indicated a stronger reduction for PFOS in comparison to, for example, PFOA. However, long-term monitoring is needed to assess the treatment&#8217;s efficiency over time.</p>
This technical note summarises major changes in the updated version of SF Box, which is part of t... more This technical note summarises major changes in the updated version of SF Box, which is part of the SCORE – the Multi-Criteria Decision Analysis method for decision support in soil remediation projects. SCORE stands for the Sustainable Choice Of REmediation and SF Box stands for Soil Function toolBox. The SF Box tool has been developed for soil function assessment to complement environmental risk assessments, in order to increase awareness of decision-makers for inherent soil qualities other than concentration of contaminants and their availability/mobility, which are critical for proper soil functioning, e.g. availability of water and nutrients for soil organisms, but often ignored in remediation projects (driven by protection of the soil environment with ambition to recover ecosystem functions) in Sweden. The tool is based on a scoring method using soil quality indicators (SQIs) for assessing (I) the soil’s capacity to perform its functions in its own reference state of being ‘cle...
Environmental Science & Technology, 2016
Environmental Toxicology and Chemistry, 2022
Biogeochemistry, Jul 12, 2007
Applied Geochemistry, Mar 1, 2009
Applied Geochemistry, May 1, 2022
In all countries in Europe, and probably the rest of the world, soil quality criteria (SQC) are b... more In all countries in Europe, and probably the rest of the world, soil quality criteria (SQC) are based on total concentrations of contaminants. Indeed, the total concentration is an indicator of toxicity, but vast amounts of laboratory and field studies have shown that biological effects are not directly related to the total concentration. Instead, soil organisms respond to the fraction of contaminant that is biologically available. One way to deal with bioavalability is to use biological tests directly, with the aim to cover relevant organisms and/or soil functions. Although being of high relevance, biological tests are generally costly, time consuming, and complicated to perform and evaluate, which limits their use in practical risk assessments. In this respect, chemical methods offer an alternative, having the potential to be faster, cheaper and easier to commercialise. However, before any chemical bioavailability method can be used in a risk assessment framework, a corresponding ...
Mercury (Hg) cannot be destroyed therefore only two principal processes are available for the tre... more Mercury (Hg) cannot be destroyed therefore only two principal processes are available for the treatment of Hg-contaminated soil: 1) separation of Hg from soil (through wet-sieving and/or chemical e ...
Biogeochemistry, Jan 23, 2008
<p>&#160;Per- and polyfluoroalkyl substances (PFAS) are fluorinated organic... more <p>&#160;Per- and polyfluoroalkyl substances (PFAS) are fluorinated organic chemicals that have extensively been used for more than five decades worldwide, resulting in their ubiquitous spreading . In the light of their toxicity, recalcitrance and bioaccumulation potential, their use and disposal are increasingly being limited. Groundwater is one of the environmental pathways critical for PFAS dispersal and subsequent human exposure. Case studies on PFAS groundwater contamination are lacking and remediation efforts applied in full-scale are limited. In this context, the main objective of this study was to quantify the extent of PFAS contamination in the subsurface and evaluate the effectiveness of a trap-and-treat <em>in-situ</em> soil remediation method with the use of colloidal activated carbon. A PFAS-contaminated site was selected for investigation in Sweden, that has previously been used for fire-fighting training with PFAS-containing aqueous fire-fighting foam (AFFF).</p><p><strong>&#160;</strong>PFAS concentrations and hydrological properties of the contaminated site were investigated. Groundwater was sampled through five monitoring wells, while surface water samples were collected at four different locations in a stream adjacent to the site monthly-bimonthly. PFAS concentrations were quantified for 11 individual PFASs. Colloidal activated carbon was injected in the subsurface, aiming for a good distribution of the sorbents in the treatment zone. Monitoring wells were drilled upstream and downstream to the injection well, identifying variations in concentrations through time. Total oxidizable precursor concentrations were also quantified in two observation wells. Other parameters that were monitored in the wells included pH, conductivity and metals concentrations. Groundwater levels were measured by manual sounding as well as by automated logging with barometric compensation. Aquifer characteristics were defined by slug tests and the site&#8217;s geological characteristics were investigated.</p><p>Prior treatment, groundwater concentrations of &#8721;PFASs were up to 24 &#956;g L<sup>-1</sup>, while two significant hotspots were identified. &#8721;PFASs concentrations decreased by ~74% based on the original concentration within and directly downstream of the treatment zone approximately three months after applying the colloidal activated carbon. Differences in the PFAS composition profile after injection, indicated a stronger reduction for PFOS in comparison to, for example, PFOA. However, long-term monitoring is needed to assess the treatment&#8217;s efficiency over time.</p>
This technical note summarises major changes in the updated version of SF Box, which is part of t... more This technical note summarises major changes in the updated version of SF Box, which is part of the SCORE – the Multi-Criteria Decision Analysis method for decision support in soil remediation projects. SCORE stands for the Sustainable Choice Of REmediation and SF Box stands for Soil Function toolBox. The SF Box tool has been developed for soil function assessment to complement environmental risk assessments, in order to increase awareness of decision-makers for inherent soil qualities other than concentration of contaminants and their availability/mobility, which are critical for proper soil functioning, e.g. availability of water and nutrients for soil organisms, but often ignored in remediation projects (driven by protection of the soil environment with ambition to recover ecosystem functions) in Sweden. The tool is based on a scoring method using soil quality indicators (SQIs) for assessing (I) the soil’s capacity to perform its functions in its own reference state of being ‘cle...
Environmental Science & Technology, 2016
Environmental Toxicology and Chemistry, 2022
Biogeochemistry, Jul 12, 2007
Applied Geochemistry, Mar 1, 2009
Applied Geochemistry, May 1, 2022
In all countries in Europe, and probably the rest of the world, soil quality criteria (SQC) are b... more In all countries in Europe, and probably the rest of the world, soil quality criteria (SQC) are based on total concentrations of contaminants. Indeed, the total concentration is an indicator of toxicity, but vast amounts of laboratory and field studies have shown that biological effects are not directly related to the total concentration. Instead, soil organisms respond to the fraction of contaminant that is biologically available. One way to deal with bioavalability is to use biological tests directly, with the aim to cover relevant organisms and/or soil functions. Although being of high relevance, biological tests are generally costly, time consuming, and complicated to perform and evaluate, which limits their use in practical risk assessments. In this respect, chemical methods offer an alternative, having the potential to be faster, cheaper and easier to commercialise. However, before any chemical bioavailability method can be used in a risk assessment framework, a corresponding ...