Evaluation of Water Quality Impact Caused by Common Hazardous Waste Landfill Facility in Gummidipoondi, Tamilnadu- India

The aim of the study was to evaluate the water quality impact caused due to the operations of common hazardous waste landfill facility (CHWLF) in Gummidipoondi industrial estate, Tiruvallur district, Tamilnadu, India. The watershed area of the hazardous waste landfill facility was delineated using Arc-GIS tools and prediction of ground water flow direction was carried out using three-dimensional ground water flow model using VISUAL MODFLOW software. The water quality analysis was performed in the upstream and downstream directions of the project site and the results showed that all the tested parameters were within the BIS 10500:2012 drinking water limits, except pH which showed slightly acidic characteristics in certain locations. The tested water samples mostly belonged to the Ca + Mg-HCO3’ type as classified using the multivariate analysis method using piper diagram. Co-relation between the water quality parameters were determined using statistical analysis of Pearson's correlation coefficient (r) values.

Water quality impact from shrimp farming effluents in a tropical estuary

Shrimp farms cause environmental impacts in coastal ecosystems, compromising water quality by discharging effluents rich in nutrients and organic matter. The impacts of shrimp farming are often investigated by the unit effect of a farm. In this study, a harvest time series generator is used to analyze the impact of the synergistic effect of several shrimp farm harvests in a tropical estuary. Two other scenarios with harvests concentrated during spring and neap tides were also analyzed, showing waste management techniques that can reduce the impact of shrimp aquaculture on coastal areas. A hydrodynamic circulation and water quality model were implemented to evaluate the dispersion of pollutants using different discharge combinations. The harvesting scenarios were compared to a scenario without the activity. Results indicate that shrimp farming is not the main anthropogenic source of pollution in the estuary studied. There were no significant differences in the average and maximum variations in nutrient and organic matter concentrations between the different management techniques.

An Experimental Study on Mechanisms for Sediment Transformation Due to Riverbank Collapse

Riverbank erosion is a natural process in rivers that can become exacerbated by direct and indirect human impacts. Unfortunately, riverbank degradation can cause societal impacts such as property loss and sedimentation of in-stream structures, as well as environmental impacts such as water quality impact. The frequency, magnitude, and impact of riverbank collapse events in China and worldwide are forecasted to increase under climate change. To understand and mitigate the risk of riverbank collapse, experimental/field data in real conditions are required to provide robust calibration and validation of hydraulic and mathematical models. This paper presents an experimental set of tests conducted to characterize riverbank erosion and sediment transport for banks with slopes of 45°, 60°, 75°, and 90° and quantify the amount of sediments transported by the river, deposited within the bank toe or settled in the riverbed after having been removed due to erosion. The results showed interesting comprehension about the characterization of riverbank erosion and sediment transport along the river. These insights can be used for calibration and validation of new and existing numerical models.