Investigation of the Presence, Extent and Origin of Sewage Contamination Hotspots in Urban Groundwater

• Grant number: 23/13829-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2023
• End date: July 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Juliana Gardenalli de Freitas
• Grantee: Andre Gomes Bessa Miranda
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil
• Associated research grant: 20/15434-0 - SACRE: integrated water solutions for resilient cities, AP.TEM

Abstract

Groundwater contamination is one of the main environmental problems in urban centers, damaging the population's health and quality of life. In the municipality of Bauru, monitoring carried out by CETESB reports a consistent upward trend in the concentrations of some pollutants in water samples from the Bauru Aquifer System (SAB) in recent years, especially nitrate. As one of the most common contaminants in urban groundwater, linked to failures in the sewage system, nitrate has high solubility and chemical stability, favoring its permanence for long periods and over a wide range. Because it originates from a non-point source, its characterization is often complex and costly. Most studies involving this type of contamination are based on data collected from production wells, and there is a lack of knowledge about the distribution of sewage contamination in urban areas, especially in shallow, unsaturated zones. However, in order to be able to think of ways to control and minimize the impacts of this type of contamination, it is necessary to understand its distribution and behavior with greater spatial and temporal resolution. Against this backdrop, the aim is to evaluate the distribution and identify areas of greater concentration of contaminant mass (hotspots) from diffuse sources of domestic sewage in the underground environment, in an urban area in Bauru. In conjunction with the Thematic Project SACRE: Integrated solutions for resilient cities (Process: 20/15434-0), the results can support the development of pollution control technologies and strategies, as well as public policies to mitigate the effects of contamination. They can also support improvements and maintenance in basic sanitation services, with a view to human well-being and the conservation of natural resources.