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Mohamed Draoui, Abdelmalek Essaâdi University (Morocco)
Bartolomé Andreo-Navarro, Malaga University (Spain)
Kamal Targuisti El Khalifi, Abdelmalek Essaâdi University (Morocco)
Jamal Stitou, Abdelmalek Essaâdi University (Morocco)
Rabie Bardai, Abdelmalek Essaâdi University (Morocco)
Ali Maate, Abdelmalek Essaâdi University (Morocco)
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To protect groundwater against deterioration of its quality by pollutant products coming from the surface, it is important to elaborate contamination risk maps of the aquifers. These take into account the intrinsic vulnerability map and the hazards map over the aquifer. The risk map is necessary to implement preventive measures for land use management.
A contamination risk map has been performed in Martil-Alila detrital aquifer, approximately 98 km2 in extension. It is one of the most important groundwater bodies in province of Tetouan, North of Morocco. Its groundwater is used for water supply in this area, mainly during the dry and summer periods. However, it is exposed to several hazards or sources of pollution related to urban, agricultural and industrial activities.
The vulnerability to contamination map of this aquifer has been obtained applying DRASTIC method for wet hydrological conditions. It shows a High degree of vulnerability through the eastern part of the aquifer where the unsaturated zone is formed by sand and gravel, and the soil has a sandy-muddy and sandy texture. The rest of the aquifer coincides with a generally argillaceous or muddy unsaturated zone and a soil of argillaceous to argillaceous-muddy texture, which results in a moderate degree of vulnerability.
The hazard map shows a Moderate class which is limited mainly to the center of the Est part of the aquifer, coinciding with the urban activities without network of cleansing. This same degree characterizes the nucleus of activity such as the gasoline stations, electrochemical unit and a station of gas load. The rest of the study are shows Low degree of hazard related to the agricultural activity and the urban zone with network of cleansing.
The superposition of the two preceding maps (intrinsic vulnerability and hazard map) permits to obtain the contamination risk map of Martil-Alila aquifer. This latter is characterized by the predominance of the Low and Moderate classes. The first one characterizes the Western part of the plain, due to the agricultural activity and urban zone with network of cleansing over the Moderate vulnerability degree of the aquifer. However, in the Eastern part of the aquifer, urban, industrial zones and agricultural activities are over highly vulnerable areas of the aquifer, which results Moderate risk to contamination.
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