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After studying the waste management opportunities in small and medium companies of natural casings, composting has proved more viable and cost effective solution for the valorization of these types of waste, but its feasibility depends on the final product value. This paper investigated a pilot scale program for the windrow co-composting of natural casings waste with sheep manure and dead leaves incorporation. Processing, characterization and application of the final compost were described and the final compost was analyzed for pathogens, metals, nutrients, maturity, and agronomic parameters. The results showed that all test result levels were below the limits specified in the EPA regulations published in Title 40, Section 503, of the Code of Federal Regulations (40 CFR 503). Moreover, the agronomic value tests which include nutrients, organic matter, pH, electrical conductivity, etc. showed that the compost had high organic-matter content and low salt content, all of which indicate good compost characteristics. The ratio of nitrogen (N), phosphorus (P), and potassium (K), or NPK ratio, was measured at 1.6–0.9–0.7. Reported units are consistent with those found on fertilizer formulations. [ABSTRACT FROM AUTHOR]

Composting is considered as a sustainable strategy for organic waste management, yet the choice of suitable technology makes its sustainability disputable. The subject under investigation concerns the sustainability assessment of large-scale composting technologies using surrogate weights and PROMETHEE method. In this regard, six composting systems, including open, enclosed and reactor technologies, were evaluated in terms of environmental, financial/economic, social and technical criteria. Firstly, ten internationally endorsed experts assigned their preferred rankings for the groups of criteria as well as the sub-criteria. The application of the additive combination of sum and reciprocal weight functions on these rankings allowed calculating the corresponding weights for each group of criteria and each sub-criterion. Secondly, the PROMETHEE method was applied, taking into account the alternatives' performance with regards to each criterion, to calculate the outranking flows for each alternative. The obtained rankings revealed that reactor technologies are more sustainable than enclosed technologies, which in turn are more sustainable than open technologies. Overall, the rotating drum is ranked as the most sustainable composting technology achieving the optimal balance among the environmental, financial/economic, social, and technical criteria. However, the turned windrow seems to be the least sustainable composting technology. Image 1 • Sustainability assessment of large-scale composting technologies was investigated. • Surrogate weights and PROMETHEE method were used. • Environmental, economic, social and technical criteria were considered. • Reactor technologies are more sustainable than enclosed and open technologies. • Rotating drum achieved the optimal balance among the considered criteria. [ABSTRACT FROM AUTHOR]

This study aims to assess the evolution of seawater intrusion between 1992 and 2011 periods in the coastal aquifers of Oualidia. To achieve this objective, the combination of geoelectrical and hydrochemical methods was adopted. Apparent resistivity maps, using 74 Vertical Electrical Sounding (VES) performed on 1992, allowed to distinguish two different zones. The conductive one, with apparent resistivity ranging between 4 and 86 Ω·m, is limited to 1 km with respect to the ocean. Meanwhile, the resistant one is much farther from the coastline. Besides, results of Electrical Resistivity Tomography (ERT) profiles performed during 2011 are in good agreement with those obtained by apparent resistivity maps. The ERT profiles show a conductive level characterized by low resistivity below 30 Ω·m assigned to seawater intrusion effect. Moreover, hydrochemical analysis, performed on 19 wells during three different periods, on June, December 2010 and May 2011, indicates that the most affected part with marine waters was at that time localized in the first kilometer from the ocean, with high amounts of Na + and Cl − ions. Beyond this fringe, mineralization becomes very weak. Overall, the comparison of old VES with recent ERT coupled with hydrochemical results suggest no important evolution of the salt wedge since 1992. [ABSTRACT FROM AUTHOR]

This study aims to identify groundwater salinization origin and to determine seawater intrusion extension toward the inland in Chaouia, Morocco. To reach these objectives, firstly, 46 groundwater samples were analyzed for major chemical elements during January 2012 and, secondly, 10 electrical resistivity tomography (ERT) profiles were performed perpendicularly to the coastal fringe. Statistical analysis provided the distinction between three Clusters reflecting different hydrochemical processes. Cluster I and Cluster II-a showed a high water electrical conductivity (EC) (from 2.3 to 11.2 mS/cm) with the dominance of Na + (668 mg/L on average) and Cl − (1735 mg/L on average) ions as a consequence of seawater intrusion. However, Cluster II-b presented low ECs (from 0.5 to 1.7 mS/cm) and Ca 2 + (99.6 mg/L on average) and HCO 3 2 − (235.2 mg/L on average) ions dominance. Water chemistry in these wells was controlled by water-rock interaction, cation exchange, and anthropogenic activities. The Hydrochemical Facies Evolution Diagram highlighted the succession of different water facies developed between intrusion and freshening phases. The formation of Na-HCO 3 facies, which characterizes the last facies of freshening phase, followed the succession of Na-Cl, MixNa-MixCl, MixCa-MixCl, MixCa-MixHCO 3 , and Na-HCO 3 . In contrast, Na-Cl facies formation, which characterizes the last facies of intrusion phase, followed the evolution of Ca-HCO 3 , Ca-MixHCO 3 , Ca-MixCl, MixCa-MixCl, MixCa-Cl, and Na-Cl. Moreover, the obtained ERT results allowed determining the extent of different hydrochemical facies and provided more details about seawater intrusion extension. The conductive level assigned to seawater contamination showed a resistivity less than 36 Ω.m, which remains limited to 3000 m from the ocean, where Na-Cl water type dominates. The seawater intrusion depth varied between 5 and 40 m from the surface. Overall, this original study in Chaouia region demonstrated the effectiveness of combining hydrochemical and ERT methods to investigate seawater intrusion, particularly in areas with restrictive water chemistry data. [ABSTRACT FROM AUTHOR]

The objective of this study is to identify the influence of different hydrochemical processes, potential salinity sources, and seawater intrusion on groundwater quality in the coastal region of Oualidia. For this purpose, chemical analyses were performed on 19 wells sampled during three campaigns: June and December, 2010 and May, 2011. Investigations were conducted to identify the significant chemical variations between different campaigns. In addition, chemical variations were controlled by two main factors, which are the distance from the coast and the morphological aspect. Furthermore, statistical analysis allows the identification of two clusters of samples. The first groups, near the ocean, are highly mineralized with dominance of Na + and Cl − ions, while the second group, much farther from the coast, are slightly mineralized with dominance of Ca 2+ and H C O 3 − ions. Besides, ionic ratio, ionic delta, saturation index, and Gibbs diagram were applied to evaluate geochemical processes responsible for groundwater mineralization. Results showed that salinity was due mainly to seawater intrusion, especially in the first kilometers from the ocean covering the first group of wells. Moreover, cation exchange between Na + , Ca 2+ , Mg 2+ , and K + , evaporation, and evaporate dissolution are principal processes, which also contribute to groundwater salinization. In overall, this investigation provided a basis of geochemical data to effectively manage groundwater resource and efficiently mitigate impacts on aquifers. [ABSTRACT FROM AUTHOR]

The coastal aquifer system of Chaouia is recognized as one of the most important aquifers in Morocco that is affected by salinization in the coastal fringe. The purpose of this study is to highlight the origin of salinization by sampling and analyzing groundwater from 44 wells for major elements. This study was carried out in May 2011. The results indicate that, in the central and downstream parts, the dominant facies are Mg 2+ , Na + and Cl − , while Ca 2+ and HCO 3 − dominate in the upstream zones. Ion exchange processes, under seawater intrusion, control the concentration of ions such as calcium, magnesium and sodium. Moreover, groundwater is oversaturated with respect to carbonate minerals (calcite and dolomite), and under-saturated with respect to evaporate minerals (gypsum, halite). The contribution of dissolved halite and gypsum in the groundwater mineralization is revealed by their positive correlation between (Na + Cl) and (Ca + SO 4 ), respectively. Furthermore, the comparison of the hydrochemical results to drinking water quality standards by World Health Organization (2008) shows that more than a half of the water sampled is not suitable for drinking purposes, especially with respect to high levels of EC, TDS, Cl − and NO 3 − . In addition, high mineralization is found to be a consequence of seawater intrusion and anthropogenic activities. [ABSTRACT FROM AUTHOR]