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The application of geotextiles as filter materials in various systems, such as biofilters, wetlands, and wastewater treatment plants, has grown significantly in recent years. The ability of these materials to support biofilm growth makes them ideal for the removal of organic and inorganic contaminants present in wastewater. The objective of this research was to analyze clogging through variations in permeability, using column tests for 80 days with two types of nonwoven geotextiles with different grammages (GT120 and GT300), as well as to study the efficiency in the removal of organic matter. A synthetic wastewater was used, allowing the specific observation of biological clogging and the treatment carried out exclusively by microorganisms. The results indicated that bioclogging was not a significant factor within the experimental period. Through the mass test, a continuous increase in biofilm growth over time was observed for both geotextiles. For scanning electron microscopic (SEM) images, GT300 presented a larger biofilm area. A higher removal of COD (80%), N (52%), and P (36%) by microorganisms present in GT300 was found, which appears to be associated with its greater thickness and weight. The higher mesh density provides a larger area for the growth of microorganisms, allowing a greater amount of biomass to establish itself and contributing to the efficient removal of pollutants. These findings highlight the potential of using geotextile filters in wastewater treatment applications, where biofilm growth can positively contribute to contaminant removal without immediately compromising permeability. [ABSTRACT FROM AUTHOR]

Soil erosion has been causing an imbalance in nature and the environment. It is mainly caused naturally but is also due to human interventions leading to desertification and possible contamination. Therefore, engineering, geography, and cartography have been allies in applying erosion models to predict, address, and remediate the impacts. Therefore, the Revised Universal Soil Loss Equation (RUSLE) and Soil and Water Assessment Tool (SWAT) linked to Geographic Information Systems (GISs) could boost decision making as tools to mitigate issues. This study applies the RUSLE and SWAT models from a geotechnical point of view to analyze a sub-watershed at Idanha-a-Nova (Portugal) over 4 years, showing a predominant erosion risk class with losses lower than 5 t.ha−1.year−1 (60 to 86%), characterized as very low risk. The modeling permitted the development of soils erosion susceptibility charts, in addition to material availability and the suitability for construction areas, exposing a replicable methodology that could contribute to minimizing environmental impacts while encouraging a more intelligent use of the land towards a greener exploration. [ABSTRACT FROM AUTHOR]

Geoenvironmental engineering involves defining solutions for complex problems, such as containment systems management, contaminant transport control, wastewater management, remediation of contaminated sites and valorization of geomaterials and wastes. In the last years, energy harvesting (EH)—or energy scavenging—methods and technologies have been developed to reduce the dependence on traditional energy sources, namely fossil fuels, and nuclear power, also responding to the increase in energy demands for human activities and to fulfill sustainable development goals. EH in geoenvironmental works and the surrounding soil and water environment includes a set of processes for capturing and accumulating energy from several sources considered wasted or unusable associated with soil dynamics; the stress and strain of geomaterials, hydraulic, vibrations, biochemical, light, heating and wind sources can be potential EH systems. Therefore, this work presents a review of the literature and critical analysis on the main opportunities for EH capturing, accumulating and use in geoenvironmental works, among basic electric concepts and mechanisms, analyzing these works in complex conditions involving biological-, chemical-, mechanical-, hydraulic- and thermal-coupled actions, concluding with the main investigation and challenges within geoenvironmental aspects for EH purposes. [ABSTRACT FROM AUTHOR]

Biomass ashes (BA) have been intensively studied as amendments for soil in earthworks. This paper aimed to geotechnically characterize BA from pines and olive trees compared to the soil from Castelo Branco, Portugal. Namely, granulometry, specific gravity, Atterberg limits and optimal compaction values were obtained and analyzed in order to valorize the residue incorporated into soils. This work is part of broader efforts to develop an alternative material that can be used in hydraulic barriers as liners and for soil reinforcement. Thus, BA can contribute to reductions in weight and plasticity, and filling properties. Further studies are needed, particularly mechanical and hydraulic performances tests. [ABSTRACT FROM AUTHOR]

Mineralogical and chemical evaluations are necessary to investigate the background and origins of materials. In terms of residues commonly produced around the world, ashes biomass stands out for its high calorific capacity and use for energy production at thermoelectrical facilities. Given current sustainability issues and new demands from society, ashes and soil from pine biomass in the Castelo Branco region were investigated to research possible anthropogenic contaminations, heavy metals among their composition, and their physic-chemical characteristics. These properties can be used to define possible valorisation methods through residue introduction into the soil for its reinforcement and liner application. The results indicated that ashes biomass could help achieve these objectives and could be introduced into the soil, due to its enrichment with pozzolanic minerals and fine granulometry, while having a low-density, which could reduce final weight; however it was considerably different from the original biomass, and contained anthropogenic contaminations and high concentrations of heavy metals. [ABSTRACT FROM AUTHOR]