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The pesticide transportation to deeper soil layers can result in groundwater contamination and, consequently, environmental issues. In this research, our objective was to investigate transport efficiency of indoxacaarb using three different soils to understand the leaching potential. The leaching experiments were performed using a 0.01 M calcium chloride solution over five consecutive days. Leachates (water) and soil samples were collected and the residues of indoxacarb were analyzed using gas chromatography mass spectrometry. The method’s accuracy was validated by conducting recovery experiments at levels ranging from 0.01 to 0.1 µg/g. The results showed that 82.67 to 84.00%, 80.67 to 82.70% and 76.68 to 78.70% of the indoxacarb applied was retained in the topsoil layer (0–10 cm) for acid, alkali and neutral soil, respectively. Its low leaching behavior, as evidenced by its retention in the topsoil layer and absence in the leachate, contributes to its limited mobility within the soil profile. The study suggests that indoxacarb has no potential for contaminating groundwater and the soil environment through leaching processes. [ABSTRACT FROM AUTHOR]

This paper demonstrates that ash composites, comprising fly ash and polyurethane, can be used to develop value-added products that exhibit an effective decrease in the leaching of coal ash inorganics to less than one-third of the Environmental Protection Agency (EPA)'s maximum contaminant level (MCL) when soaked in a water circulation system for 14 months. Furthermore, the composite blocks remain safe even with ruptured surfaces. The concept of encapsulating fly ash within ash composites by using a polar polymer to bind the fine inorganic particles, mimicking how nature does it in the original unburned coal, ensures the safety of the composite. The ash composites can be formulated to have designed mechanical, fire, and electrical properties by controlling the formulation and the density. The properties of typical density composites were produced, measured, and compared with commercial materials. This paper also demonstrates that ash composite technology can be extended to coal ash stored in ponds. Finally, a typical electric utility box cover was designed, fabricated, and test validated. The box cover has less than one-half the weight of the original box cover for the same design limits. Finally, the benefits of this ash-composite technology for product manufacturers, society, and ash producers are summarized. [ABSTRACT FROM AUTHOR]

The precipitation of sparingly soluble calcium phosphate in calcareous soils decreases the bioavailability of macronutrients, which makes their addition by way of fertilisers necessary. Sludge resulting from treating urban wastewater does not only provide significant amounts of phosphorus, but also helps lower the pH, thus increasing its bioavailability. The loss of part of soil nutrients due to irrigation or rain can contaminate groundwater. In order to assess the movement of phosphorus, a experiment was conducted on percolation columns, to which different doses of wastes were applied. The pH decreased by as much as 0.89 units, as well as the assimilable and soluble P, in intervals of 20 cm of depth, obtaining maximum values of 254 mg P kg−1 and 1455 μg P kg−1 respectively, and the P present in the leached water collected, which did not surpass 95 μg PL−1. The intent was to learn which was the majoritarian inorganic formed crystalline phase that immobilised the movement of phosphorus through the percolation column. The results obtained by the diffraction of X-rays are not conclusive, although they point to the formation of octacalcium phosphate. The diffractograms of the studied samples have similar diffraction lines to those of apatites. [ABSTRACT FROM AUTHOR]