Implementing risk-based approaches to improve drinking water quality in small water supplies in the Nordic region - barriers and solutions.

Small water supplies face similar problems worldwide, regardless of ownership or management type. Non-compliance with water quality regulations is more frequent in small supplies than in large ones, as are waterborne disease outbreaks. The new European Union Drinking Water Directive requires risk-based approach (RBA) to secure water safety as is recommended in the World Health Organization's Guidelines for drinking water quality through 'water safety plans'.

Domestic water supply in rural Greenland - sufficiency, affordability and accessibility.

Global efforts are still under way to ensure sustainable development goal 6 of providing enough clean water to sustain public health in many regions, and especially in the Arctic where the remoteness of communities and the harsh climate make water provision especially challenging. This study aimed to examine the sufficiency, accessibility, and affordability of water supplies in rural Greenland. The state of the water supply was investigated using quantitative data on infrastructure and demographics.

Impacts of climate change on metal leaching and partitioning for submarine mine tailings disposal.

At present, there are no standardised tests to assess metal leaching during submarine tailings discharge. In this study the influence of variables known to affect metal mobility and availability (dissolved organic carbon (DOC), pH, salinity, temperature, aerated/anoxic conditions) along with variables affected by the discharge conditions (flocculant concentration, suspension) were studied in bench-scale experiments. The leaching tests were developed based on the case of a copper mine by Repparfjorden, northern Norway, which is planned to re-open in 2022.

Characterisation and chemometric evaluation of 17 elements in ten seaweed species from Greenland.

Several Greenland seaweed species have potential as foods or food ingredients, both for local consumption and export. However, knowledge regarding their content of beneficial and deleterious elements on a species specific and geographical basis is lacking. This study investigated the content of 17 elements (As, Ca, Cd, Cr, Cu, Fe, Hg, I, K, Mg, Mn, Na, Ni, P, Pb, Se and Zn) in 77 samples of ten species (Agarum clathratum, Alaria esculenta, Ascophyllum nodosum, Fucus distichus, Fucus vesiculosus, Hedophyllum nigripes, Laminaria solidungula, Palmaria palmata, Saccharina latissima and Saccharina longicruris).

Comparison of 2- and 3-compartment electrodialytic remediation cells for oil polluted soil from northwest Russia.

Electrodialytic remediation is a method based on electrokinetics, in which an electric field of low intensity increases the availability of pollutants in solid waste materials. The electric field induces processes that mobilise and transport inorganic and organic pollutants. The transport of ions in the electrodialytic cell is controlled by employing ion-exchange membranes, allowing separation of the electrodes from the solids.

Evaluation of mine tailings' potential as supplementary cementitious materials based on chemical, mineralogical and physical characteristics.

In order to reduce emissions of CO from cement production and avoid severe environmental pollution from the deposition of mine waste, this study investigated the possibility of utilizing mine tailings as supplementary cementitious materials (SCM) for partially replacement of cement in concrete. This study provides a characterization study of mine tailings to evaluate their potential for contributing chemically or physically as SCM. 13 mine tailing samples were characterized in regards to chemical composition (XRF, Loss on Ignition, CaCO and pH), mineralogical content (XRD) and physical characteristics (Grain size distribution, Specific Surface Area, SEM-analysis).

Lability of toxic elements in Submarine Tailings Disposal: The relationship between metal fractionation and metal uptake by sandworms (Alitta virens).

Mine tailings from the iron ore mine Sydvaranger Gruve have been deposited in Bøkfjorden, Northern Norway, for >40 years. This study investigates the environmental impacts of submarine tailings disposal one year after the cessation of the mine by combining analyses of total metal concentrations (nitric acid digestion) and metal fractionation patterns (sequential extraction procedure) of sediments with the metal uptake (bioassays) by sandworms (Alitta virens) exposed to Bøkfjorden sediment. The analyses focused on metals (As, Cd, Cr, Cu, Fe, Ni, Pb, Zn) in sediment cores retrieved from a horizontal transect of the fjord.

Electrokinetics applied in remediation of subsurface soil contaminated with chlorinated ethenes - A review.

Electrokinetics is being applied in combination with common insituremediation technologies, e.g. permeable reactive barriers, bioremediation and in-situ chemical oxidation, to overcome experienced limitations in remediation of chlorinated ethenes in low-permeable subsurface soils.

Electrodialytic per- and polyfluoroalkyl substances (PFASs) removal mechanism for contaminated soil.

Contamination of soils with per- and polyfluoroalkyl substances (PFASs) is a global problem, in particular at fire-fighter training sites due to the usage of PFAS-containing aqueous fire-fighting foams (AFFFs). In this study, an electrodialytic remediation method was applied for the first time to remove PFASs from contaminated soil. The electrodialytic remediation system was evaluated in a laboratory-scale experiment with current densities of 0.

Comparison of two- and three-compartment cells for electrodialytic removal of heavy metals from contaminated material suspensions.

Electrodialytic remediation can be applied to remove heavy metals from contaminated particulate materials in suspension. The applied electric current is the cleaning agent and the heavy metals are removed by electromigration. In this study, a two-compartment cell was compared to a three-compartment cell, for several contaminated materials such as soils, sediments, mine tailings and ashes and totally 20 experiments were conducted.

Electrodialytic treatment of Greenlandic municipal solid waste incineration fly ash.

In Greenland, fly ash could contribute as a local resource in construction as a substitute for cement in concrete or clay in bricks, if the toxicity of the ash is reduced. In this study, fly ash from three different Greenlandic waste incinerators were collected and subjected to electrodialytic treatment for removal of heavy metals with the aim of enabling reuse of the fly ashes. Seven electrodialytic experiments treating up to 2.

Applying multivariate analysis for optimising the electrodialytic removal of Cu and Pb from shooting range soils.

Multivariate analysis was applied to simultaneously evaluate the influence of soil properties and experimental variables on electrodialytic removal of Cu and Pb from three shooting range soils. Both stationary and stirred set-ups in laboratory scale were tested, representing in-situ and ex-situ remediation conditions, respectively. Within the same experimental space, higher removal of the targeted metals, Cu and Pb, were observed in the stirred set-up (9-81%) compared to the stationary set-up (0-41%).

The influence of Magnafloc10 on the acidic, alkaline, and electrodialytic desorption of metals from mine tailings.

Repparfjorden in northern Norway has been partly designated for submarine mine tailings disposal when the adjacent Cu mine re-opens in 2019. In order to increase sedimentation, the flocculant, Magnafloc10 is planned to be added to the mine tailings prior to discharge into the fjord. This study investigated the feasibility of reducing the Cu concentrations (375 mg/kg) in the mine tailings by applying electrodialytic extraction, including potential optimisation by adding Magnafloc10.

Influence of electrode placement for mobilising and removing metals during electrodialytic remediation of metals from shooting range soil.

Electrodialytic remediation was applied to a shooting range soil to investigate the influence of electrode placement on the removal and binding of metals during the treatment. The set-up was based on a 2-compartment cell, in which the cathode was separated from the soil by a cation exchange membrane and the anode was placed directly in the soil, thereby introducing protons and oxygen directly in the soil. Mobilisation of metals from less available fractions (oxidisable and residual) in the soil occurred, due to oxidation/dissolution of insoluble/soluble organic matter and possibly metal oxides in the residual fraction.

Effect of long-term electrodialytic soil remediation on Pb removal and soil weathering.

Weathering of soil minerals during long-term electrochemical soil remediation was evaluated for two different soils: an industrially Pb contaminated soil with high carbonate content and an unpolluted soil with low carbonate content. A constant current of 5 mA was applied for 842 days, and sampling was made 22 times during the treatment. The overall qualitative mineral composition was unaffected by electrodialysis, except for calcite removal which was complete.

Electrodialytic extraction of Cr from water-washed MSWI fly ash by changing pH and redox conditions.

Electrodialytic process offers a range of possibilities to waste management by electrodialytic separation (EDS) of heavy metals, depending on how the process is designed. Using three EDS cell setups (two two-compartment and one three-compartment) and their combinations, the extraction of Cr from municipal solid waste incineration fly ash by changing pH and redox conditions was investigated in the present work. The experiments were designed into single, two and three steps, based on the number of setups (by changing EDS cells) or effective setups (by shifting working electrode pairs) used.

Comparison of different MSWI fly ash treatment processes on the thermal behavior of As, Cr, Pb and Zn in the ash.

To reduce heavy metal leaching and stabilize municipal solid waste incineration (MSWI) fly ash, different methods and combination of methods were tested: water washing, electrodialytic separation and thermal treatment at 1000°C. A comparison of heavy metal concentration and leaching levels of As, Cr, Pb and Zn for the different untreated and treated ashes was made. The results showed that minimizing leaching to meet the limiting values of the all the studied heavy metals can be obtained at the same time by combining water washing, electrodialytic separation and thermal treatment.

Long-term dispersion and availability of metals from submarine mine tailing disposal in a fjord in Arctic Norway.

Mining of Cu took place in Kvalsund in the Arctic part of Norway in the 1970s, and mine tailings were discharged to the inner part of the fjord, Repparfjorden. Metal speciation analysis was used to assess the historical dispersion of metals as well as their potential bioavailability from the area of the mine tailing disposal. It was revealed that the dispersion of Ba, Cr, Ni, Pb and Zn from the mine tailings has been limited.

Simultaneous electrodialytic removal of PAH, PCB, TBT and heavy metals from sediments.

Contaminated sediments are remediated in order to protect human health and the environment, with the additional benefit of using the treated sediments for other activities. Common for many polluted sediments is the contamination with several different pollutants, making remediation challenging with the need of different remedial actions for each pollutant. In this study, electrodialytic remediation (EDR) of sediments was found effective for simultaneous removal of heavy metals and organic pollutants for sediments from Arctic regions - Sisimiut in Greenland and Hammerfest in Norway.

Comparison of phosphorus recovery from incineration and gasification sewage sludge ash.

Incineration of sewage sludge is a common practice in many western countries. Gasification is an attractive option because of its high energy efficiency and flexibility in the usage of the produced gas. However, they both unavoidably produce sewage sludge ashes, a material that is rich in phosphorus, but which is commonly landfilled or used in construction materials.

Treatment of Arctic wastewater by chemical coagulation, UV and peracetic acid disinfection.

Conventional wastewater treatment is challenging in the Arctic region due to the cold climate and scattered population. Thus, no wastewater treatment plant exists in Greenland, and raw wastewater is discharged directly to nearby waterbodies without treatment. We investigated the efficiency of physicochemical wastewater treatment, in Kangerlussuaq, Greenland.

Sequential electrodialytic recovery of phosphorus from low-temperature gasification ashes of chemically precipitated sewage sludge.

Phosphorus recycling from secondary materials like sewage sludge ashes offers an alternative to mining of phosphates from primary resources and a mean to counteract the current phosphorous rock depletion concern. A separation of P from the bulk ash is normally required, due to its low plant availability and the presence of heavy metals. Previously, more than 80% of P was recovered from incineration sewage sludge ashes using a two-compartment electrodialytic cell.

Electrodialytic remediation of municipal solid waste incineration residues using different membranes.

In the present work, three different commercial membrane brands were used in an identical electrodialytic cell setup and operating conditions, in order to reduce the leaching of metals and salt anions of two types of municipal solid waste incineration residues: air pollution control residues of a semi-dry flue-gas cleaning system and fly ashes from a plant with wet flue-gas cleaning system. The results showed a general reduction of the leaching in both residues after ED remediation. For the following elements, the leaching was found to be different after ED treatment depending on the membrane used, with statistical significance: • Air pollution control residues of the semi-dry flue-gas cleaning system: Cr, Cu, Ni, Pb, Zn; • Fly ashes from a plant with wet flue-gas cleaning system: Al, Ba, Cu, Ni, Zn, Cl, SO.

Screening of heavy metal containing waste types for use as raw material in Arctic clay-based bricks.

In the vulnerable Arctic environment, the impact of especially hazardous wastes can have severe consequences and the reduction and safe handling of these waste types are therefore an important issue. In this study, two groups of heavy metal containing particulate waste materials, municipal solid waste incineration (MSWI) fly and bottom ashes and mine tailings (i.e.