Geophysical investigation of glass 'hotspots' in glass dumps as potential secondary raw material sources.

This study investigates the potential for Electrical Resistivity Tomography (ERT) to detect buried glass 'hotspots' in a glass waste dump based on results from an open glass dump investigated initially. This detection potential is vital for excavation and later use of buried materials as secondary resources. After ERT, test pits (TPs) were excavated around suspected glass hotspots and physico-chemical characterisation of the materials was done. Hotspots were successfully identified as regions of high resistivity (>8000 Ωm) and were thus confirmed by TPs which indicated mean glass composition of 87.2% among samples (up to 99% in some). However, high discrepancies in material resistivities increased the risk for introduction of artefacts, thus increasing the degree of uncertainty with depth, whereas similarities in resistivity between granite bedrock and crystal glass presented data misinterpretation risks. Nevertheless, suitable survey design, careful field procedures and caution exercised by basing data interpretations primarily on TP excavation observations generated good results particularly for near-surface materials, which is useful since glass waste dumps are inherently shallow. Thus, ERT could be a useful technique for obtaining more homogeneous excavated glass and other materials for use as secondary resources in metal extraction and other waste recycling techniques while eliminating complicated and often costly waste sorting needs.

Pilot scale aided-phytoremediation of a co-contaminated soil.

A pilot scale experiment was conducted to investigate the aided-phytoextraction of metals and the aided-phytodegradation of petroleum hydrocarbons (PHC) in a co-contaminated soil. First, this soil was amended with compost (10% w/w) and assembled into piles (Unp-10%C). Then, a phyto-cap of Medicago sativa L. either in monoculture (MS-10%C) or co-cropped with Helianthus annuus L. as companion planting (MSHA-10%C) was sown on the topsoil. Physico-chemical parameters and contaminants in the soil and its leachates were measured at the beginning and the end of the first growth season (after five months). In parallel, residual soil ecotoxicity was assessed using the plant species Lepidium sativum L. and the earthworm Eisenia fetida Savigny, 1826, while the leachate ecotoxicity was assessed using Lemna minor L. After 5months, PH C10-C40, PAH-L, PAH-M PAH-H, Pb and Cu concentrations in the MS-10%C soil were significantly reduced as compared to the Unp-10%C soil. Metal uptake by alfalfa was low but their translocation to shoots was high for Mn, Cr, Co and Zn (transfer factor (TF) >1), except for Cu and Pb. Alfalfa in monoculture reduced electrical conductivity, total organic C and Cu concentration in the leachate while pH and dissolved oxygen increased. Alfalfa co-planting with sunflower did not affect the extraction of inorganic contaminants from the soil, the PAH (M and H) degradation and was less efficient for PH C10-C40 and PAH-L as compared to alfalfa monoculture. The co-planting reduced shoot and root Pb concentrations. The residual soil ecotoxicity after 5months showed a positive effect of co-planting on L. sativum shoot dry weight (DW) yield. However, high contaminant concentrations in soil and leachate still inhibited the L. sativum root DW yield, earthworm development, and L. minor growth rate.

Fractionation of Pb and Cu in the fine fraction (<10 mm) of waste excavated from a municipal landfill.

The fractionation of metals in the fine fraction (<10 mm) of excavated waste from an Estonian landfill was carried out to evaluate the metal (Pb and Cu) contents and their potential towards not only mobility but also possibilities of recovery/extraction. The fractionation followed the BCR (Community Bureau of Reference) sequential extraction, and the exchangeable (F1), reducible (F2), oxidizable (F3) and residual fractions were determined. The results showed that Pb was highly associated with the reducible (F2) and oxidizable (F3) fractions, suggesting the potential mobility of this metal mainly when in contact with oxygen, despite the low association with the exchangeable fraction (F1). Cu has also shown the potential for mobility when in contact with oxygen, since high associations with the oxidizable fraction (F3) were observed. On the other hand, the mobility of metals in excavated waste can be seen as beneficial considering the circular economy and recovery of such valuables back into the economy. To conclude, not only the total concentration of metals but also a better understanding of fractionation and in which form metals are bound is very important to bring information on how to manage the fine fraction from excavated waste both in terms of environmental impacts and also recovery of such valuables in the economy.

Hunting for valuables from landfills and assessing their market opportunities A case study with Kudjape landfill in Estonia.

Landfill mining is an alternative technology that merges the ideas of material recycling and sustainable waste management. This paper reports a case study to estimate the value of landfilled materials and their respective market opportunities, based on a full-scale landfill mining project in Estonia. During the project, a dump site (Kudjape, Estonia) was excavated with the main objectives of extracting soil-like final cover material with the function of methane degradation. In total, about 57,777 m3 of waste was processed, particularly the uppermost 10-year layer of waste. Manual sorting was performed in four test pits to determine the detailed composition of wastes. 11,610 kg of waste was screened on site, resulting in fine (<40 mm) and coarse (>40 mm) fractions with the share of 54% and 46%, respectively. Some portion of the fine fraction was sieved further to obtain a very fine grained fraction of <10 mm and analyzed for its potential for metals recovery. The average chemical composition of the <10 mm soil-like fraction suggests that it offers opportunities for metal (Cr, Cu, Ni, Pb, and Zn) extraction and recovery. The findings from this study highlight the importance of implementing best available site-specific technologies for on-site separation up to 10 mm grain size, and the importance of developing and implementing innovative extraction methods for materials recovery from soil-like fractions.

Characterisation of excavated fine fraction and waste composition from a Swedish landfill.

The present research studies the characterisation and the physico-chemical properties of an excavated fine fraction (<10 mm) from a Swedish landfill, the Högbytorp. The results showed that the fine fraction represents 38% by mass of the total excavated wastes and it contains mainly soil-type materials and minerals. Higher concentrations of zinc, copper, barium and chromium were found with concentrations higher than the Swedish Environmental Protection Agency (EPA) for contaminated soil. The found moisture and organic contents of the fine fraction were 23.5% and 16.6%, respectively. The analysed calorific value (1.7 MJ kg-1), the potential of CH4 (4.74 m3 t-1 dry matter) and Total Organic Carbon (TOC) (5.6%) were low and offer low potential of energy. Sieving the fine fraction further showed that 80% was smaller than 2 mm. The fine represents a major fraction at any landfill (40%-70%), therefore, characterising the properties of this fraction is essential to find the potential of reusing/recycling or safely redisposing.

Effect of Medicago sativa L. and compost on organic and inorganic pollutant removal from a mixed contaminated soil and risk assessment using ecotoxicological tests.

Several Gentle Remediation Options (GRO), e.g., plant-based options (phytoremediation), singly and combined with soil amendments, can be simultaneously efficient for degrading organic pollutants and either stabilizing or extracting trace elements (TEs). Here, a 5-month greenhouse trial was performed to test the efficiency of Medicago sativa L., singly and combined with a compost addition (30% w/w), to treat soils contaminated by petroleum hydrocarbons (PHC), Co and Pb collected at an auto scrap yard. After 5 months, total soil Pb significantly decreased in the compost-amended soil planted with M. sativa, but not total soil Co. Compost incorporation into the soil promoted PHC degradation, M. sativa growth and survival, and shoot Pb concentrations [3.8 mg kg(-1) dry weight (DW)]. Residual risk assessment after the phytoremediation trial showed a positive effect of compost amendment on plant growth and earthworm development. The O2 uptake by soil microorganisms was lower in the compost-amended soil, suggesting a decrease in microbial activity. This study underlined the benefits of the phytoremediation option based on M. sativa cultivation and compost amendment for remediating PHC- and Pb-contaminated soils.

The Occurrence of Veterinary Pharmaceuticals in the Environment: A Review.

It is well known that there is a widespread use of veterinary pharmaceuticals and consequent release into different ecosystems such as freshwater bodies and groundwater systems. Furthermore, the use of organic fertilizers produced from animal waste manure has been also responsible for the occurrence of veterinary pharmaceuticals in agricultural soils. This article is a review of different studies focused on the detection and quantification of such compounds in environmental compartments using different analytical techniques. Furthermore, this paper reports the main challenges regarding veterinary pharmaceuticals in terms of analytical methods, detection/quantification of parent compounds and metabolites, and risks/toxicity to human health and aquatic ecosystems. Based on the existing literature, it is clear that only limited data is available regarding veterinary compounds and there are still considerable gaps to be bridged in order to remediate existing problems and prevent future ones. In terms of analytical methods, there are still considerable challenges to overcome considering the large number of existing compounds and respective metabolites. A number of studies highlight the lack of attention given to the detection and quantification of transformation products and metabolites. Furthermore more attention needs to be given in relation to the toxic effects and potential risks that veterinary compounds pose to environmental and human health. To conclude, the more research investigations focused on these subjects take place in the near future, more rapidly we will get a better understanding about the behavior of these compounds and the real risks they pose to aquatic and terrestrial environments and how to properly tackle them.

Photo-Fenton and Fenton Oxidation of Recalcitrant Wastewater from the Wooden Floor Industry.

There is a need for development of on-site wastewater treatment technologies suitable to "dry-process" industries, such as the wooden floor sector. Due to the nature of their activities, these industries generate low volumes of highly polluted and recalcitrant wastewaters due to washing and cleaning surfaces and machinery. Advanced oxidation processes such as Fenton and photo-Fenton are potentially feasible options for the treatment of wastewaters with not easily biodegradable pollutants. The wastewater from a wooden floor industry with initial COD value of 4956 mg/L and TOC value of 2730 mg/L was treated with Fenton (Fe/H2O2) and photo-Fenton (Fe/H2O2/UV) applying a 2-level full-factorial experimental design. The highest removals of COD and TOC (79% and 62% respectively) were achieved when photo-Fenton was applied. In conclusion, Fenton and photo-Fenton are promising treatment options for these highly recalcitrant wastewaters, photo-Fenton being a more promising option according to the results.

Searching for solutions to mitigate greenhouse gas emissions by agricultural policy decisions--Application of system dynamics modeling for the case of Latvia.

European Union (EU) Member States have agreed to limit their greenhouse gas (GHG) emissions from sectors not covered by the EU Emissions Trading Scheme (non-ETS). That includes also emissions from agricultural sector. Although the Intergovernmental Panel on Climate Change (IPCC) has established a methodology for assessment of GHG emissions from agriculture, the forecasting options are limited, especially when policies and their interaction with the agricultural system are tested. Therefore, an advanced tool, a system dynamics model, was developed that enables assessment of effects various decisions and measures have on agricultural GHG emissions. The model is based on the IPCC guidelines and includes the main elements of an agricultural system, i.e. land management, livestock farming, soil fertilization and crop production, as well as feedback mechanisms between the elements. The case of Latvia is selected for simulations, as agriculture generates 22% of the total anthropogenic GHG emissions in the country. The results demonstrate that there are very limited options for GHG mitigation in the agricultural sector. Thereby, reaching the non-ETS GHG emission targets will be very challenging for Latvia, as the level of agricultural GHG emissions will be exceeded considerably above the target levels. Thus, other non-ETS sectors will have to reduce their emissions drastically to "neutralize" the agricultural sector's emissions for reaching the EU's common ambition to move towards low-carbon economy. The developed model may serve as a decision support tool for impact assessment of various measures and decisions on the agricultural system's GHG emissions. Although the model is applied to the case of Latvia, the elements and structure of the model developed are similar to agricultural systems in many countries. By changing numeric values of certain parameters, the model can be applied to analyze decisions and measures in other countries.

Significance of environmental dredging on metal mobility from contaminated sediments in the Oskarshamn Harbor, Sweden.

Metals are often seen as immobile in bottom sediments as long as these environmental sinks remain undisturbed. The aim of this paper was to evaluate the potential metal mobility due to resuspension under pseudo-dredging conditions of contaminated sediments in the Oskarshamn Harbor that are likely to be dredged as part of a remediation program established in Sweden. To address this concern, mixtures of water slurries were sampled from pore, leaching, and surface water over a period of nearly 36 d, and the major ions and trace metal concentrations determined. The results of this study pointed out the potential mobility and toxicity of metals posed by temporary changes during dredging operations, and highlighted the potential release of Cu, Pb, Zn, Mn, and Ni to the environment. Among the toxic metals, regarding pre and post dredging, Cu and Pb significantly demonstrated to be in ionic form, apparently because of dissolution of Fe-Mn oxy/hydroxides and decomposition of organic matter.

Valorization of solid waste products from olive oil industry as potential adsorbents for water pollution control--a review.

The global olive oil production for 2010 is estimated to be 2,881,500 metric tons. The European Union countries produce 78.5% of the total olive oil, which stands for an average production of 2,136,000 tons. The worldwide consumption of olive oil increased of 78% between 1990 and 2010. The increase in olive oil production implies a proportional increase in olive mill wastes. As a consequence of such increasing trend, olive mills are facing severe environmental problems due to lack of feasible and/or cost-effective solutions to olive-mill waste management. Therefore, immediate attention is required to find a proper way of management to deal with olive mill waste materials in order to minimize environmental pollution and associated health risks. One of the interesting uses of solid wastes generated from olive mills is to convert them as inexpensive adsorbents for water pollution control. In this review paper, an extensive list of adsorbents (prepared by utilizing different types of olive mill solid waste materials) from vast literature has been compiled, and their adsorption capacities for various aquatic pollutants removal are presented. Different physicochemical methods that have been used to convert olive mill solid wastes into efficient adsorbents have also been discussed. Characterization of olive-based adsorbents and adsorption mechanisms of various aquatic pollutants on these developed olive-based adsorbents have also been discussed in detail. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed.

Speciation of metals in contaminated sediments from Oskarshamn Harbor, Oskarshamn, Sweden.

Bottom sediments in coastal regions have been considered the ultimate sink for a number of contaminants, e.g., toxic metals. In this current study, speciation of metals in contaminated sediments of Oskarshamn harbor in the southeast of Sweden was performed in order to evaluate metal contents and their potential mobility and bioavailability. Sediment speciation was carried out by the sequential extraction BCR procedure for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn and the exchangeable (F1), reducible (F2), oxidizable (F3), and residual (R) fractionswere determined. The results have shown that Zn and Cd were highly associated with the exchangeable fraction (F1) with 42­58 % and 43­46 %, respectively, of their total concentrations in the mobile phase. The assessment of sediment contamination on the basis of quality guidelines established by the Swedish Environmental Protection Agency (SEPA) and the Italian Ministry of Environment (Venice protocol for dredged sediments) has shown that sediments from Oskarshamn harbor are highly contaminated with toxic metals, especially Cu, Cd, Pb, Hg, As, and Zn posing potential ecological risks. Therefore, it is of crucial importance the implementation of adequate strategies to tackle contaminated sediments in coastal regions all over the world.

Characterization of municipal solid waste temporary storage sites: risks posed to surrounding areas as a consequence of fire incidents.

In this study temporary storage sites of municipal solid waste were characterized based on their potential social, health and environmental impacts as a consequence of spontaneous fires, by employing Boolean as well as weighted-linear-combination approaches in connection with various fuzzy set functions of population density around the storage sites. Sweden was used as the case study and data from 105 storage sites were analysed; of these, 38 were identified to be posing high risk for downwind residing population. Furthermore, during the past 10years, the fire frequency and the average population residing within a radius of 1, 2, and 3km were found to be comparatively higher for storage sites owned by private companies than for those owned by municipalities. The study provided first-cut information of poorly sited temporary storage sites and can help in formalizing the comprehensive risk analysis in the future.

Fires at storage sites of organic materials, waste fuels and recyclables.

During the last decade, the European Union has enforced the diversion of organic wastes and recyclables to waste management companies operating incineration plants, composting plants and recycling units instead of landfills. The temporary storage sites have been established as a buffer against fluctuations in energy demand throughout the year. Materials also need to be stored at temporary storage sites before recovery and recycling. However, regulations governing waste fuel storage and handling have not yet been developed, and, as a result, companies have engaged in risky practices that have resulted in a high number of fire incidents. In this study, a questionnaire survey was distributed to 249 of the 400 members of Avfall Sverige (Swedish Waste Management Association), which represents the waste management of 95% of the Swedish population. Information regarding 122 storage facilities owned by 69 companies was obtained; these facilities were responsible for the storage of 47% of the total treated waste (incineration + digestion + composting) in 2010 in Sweden. To identify factors related to fire frequency, the questionnaire covered the amounts of material handled and burnt per year, financial losses due to fires, storage duration, storage method and types of waste. The results show that 217 fire incidents corresponded to 170 kilotonnes of material burnt and cumulative losses of 49 million SEK (€4.3 million). Fire frequency and amount of material burnt per fire was found to be dependent upon type of management group (waste operator). Moreover, a correlation was found between fire frequency and material recycled during past years. Further investigations of financial aspects and externalities of fire incidents are recommended.

Stormwater run-off from an industrial log yard: characterization, contaminant correlation and first-flush phenomenon.

The stormwater run-off generated in an industrial log yard during eight run-off events was studied with the main focus on the transport of toxic metals. Associations between water quality constituents and potential surrogates were evaluated by correlation analysis. The first-flush phenomenon was verified by normalized M(V) curves. The results have shown that, whereas some metals such as Zn, Ba, Cd, As and Fe were always detected in these waters, others (Cr, Pb, Cu, Ni, V, Co) were not. Large variations in the water constituents' concentrations were observed, with Fe, Pb and V being the most variable ones. Concentrations of Zn and Cu in the run-off waters exceeded the values established by the Swedish environmental authorities in 100% and 97% of samples, respectively. The correlation analyses indicated TSS as a potential surrogate of Pb, V, Co, Ni, As, Ba, Cr and COD (0.949 > R > 0.808), making it reasonable to state that a treatment system with focus on TSS removal would also reduce toxic metals from these waters. The first-flush phenomenon was evident for most of the constituents. Significant differences (p < 0.05) in the first-flush magnitude of different run-off events were observed confirming that hydro-meteorological variables such as dry period, precipitation duration and average intensity play important roles. Metal loads originating from the log yard were mainly composed ofZn, Cu and Ba. Knowledge of the physicochemical characteristics, discharge dynamics and the storm variables involved in the process is a crucial step for the proposal and implementation of a stormwater management programme.

Effects from log-yard stormwater runoff on the microalgae Scenedesmus subspicatus: intra-storm magnitude and variability.

This paper describes the effects posed by stormwater runoff from an industrial log-yard on the microalgae Scenedesmus subspicatus. The effects of stormwater runoff sampled during two rain events were determined by exposing S. subspicatus cells to different concentrations (% v:v) of each sample. The effects were measured as the percentage change in growth rates in relation to a control culture after exposure times of 24, 48, 72 and 96 h. The runoff from the first rain event had no negative effects to S. subspicatus, posing in most cases growth stimulation, whereas the runoff from the second rain event inhibited algae growth. Differences in runoff physico-chemical characteristics combined with the hydrological factors of each rain event explained these opposite effects. The hypothesis of toxic first flush phenomenon was confirmed in the second rain event on the basis of normalized inhibitory effects and runoff volume. It was found that 42, 51 and 50% of the inhibitory effects during exposures of 24, 48 and 72 h were associated with the initial 4% of the total discharged volume. The fact that negative effects were observed in the two runoff events analyzed, raises concern about the potential environmental threats posed by runoff originated from wood-based industrial areas during the entire hydrological year.

Biotreatability of wastewater generated during machinery washing in a wood-based industry: COD, formaldehyde and nitrogen removal.

This paper describes biotreatability tests for treating a wastewater stream generated by wood-floor industries after cleaning and washing of machinery used to apply urea-formaldehyde resins onto wood-fiber boards. A biological system consisting of an anaerobic-intermittently aerated reactor in lab-scale was constructed. Since the investigated wastewater is intermittently generated, the system was designed to operate in batch mode. The treatment focused on removal of formaldehyde and COD, as well as the efficiency of nitrification-denitrification. The proposed cheap and relatively simple-to-operate biological system achieved COD and formaldehyde removal rates of 65+/-11% and 93+/-4% respectively. In spite of anaerobic ammonium removal and denitrification, the intermittently-aerated reactor showed poor performance for nitrification. Therefore, a better understanding of constraints for the process improvement is necessary. Regardless the constraints faced during the investigation, the proposed system can be considered feasible to partially reduce a great amount of biodegradable compounds in urea-formaldehyde-based wastewaters. However, to comply with strict threshold limits for industrial effluent discharges, the use of biological treatment combined with more advanced processes is needed to achieve a better quality of the final effluent.

Viabilidade do uso de efluentes tratados por zona de raízes na irrigação: estudo de caso na Vila Dois Rios - Ilha Grande, RJ / Constructed of the use of efluente treated by try to use it in irrigation: case study in the Vila Dois Rios - Ilha Grande, RJ

A escassez de água doce, atualmente está gerando diversos tipos de problemas, devido aos usos múltiplos e demanda crescente, principalmente para as necessidades fisiológicas humanas, e atividades econômicas como a indústria, e a irrigação para produção de alimentos. Os países mais atingidos por esta escassez buscam alternativas de. Uma destas alternativas são as águas residuárias tratadas. Atualmente a atividade humana que representa o maior consumo de água é a irrigação, o que a torna a atividade com maior necessidade de recursos alternativos. O uso de águas residuárias para a irrigação, requer uma qualidade microbiológica e físico-química que não traga riscos ao meio ambiente e principalmente à saúde pública. O presente trabalho teve como objetivo analisar a qualidade microbiológica e físico-química do efluente de um sistema de tratamento biológico de esgotos domésticos de pequeno gerador utilizando o processo de Zona de Raízes como polimento final, e a viabilidade de utilizá-lo para a irrigação de acordo com algumas diretrizes existentes para proteção à saúde pública. Foram analisados alguns parâmetros, sendo que os de maior importância para a saúde pública foram os parâmetros biológicos Escherichia coli e ovos de Helmintos, além do indicador coliforme totais. O sistema foi analisado em um período de 6 meses e demonstrou viabilidade para a aplicação e utilização do efluente na irrigação, principalmente para fins de culturas industrialmente processadas, silvicultura, plantas forrageiras, culturas frutíferas arbóreas e também de cereais.