ASSESSING THE VULNERABILITY TO POLLUTION IN THE AQUIFER’S CHARF EL AKAB (TANGIER, MOROCCO)

Assessing the vulnerability to pollution in the aquifer’s Charf El Akab (Tangier, Morocco)

Laila Achagra, Jamal Stitou El Messari, Mohamed Draoui

Faculty of Science, University of Abdelmalek Essaadi, BP 2121 Tetouan, MOROCCO

Abstract

The application of the DRASTIC’s method on Charf El Akab’s aquifer situated in the northwest of Morocco, precisely in the coastal plain between Tangiers and Asila, was made in this study. The mapping of the index DRASTIC allows us to delineate zones with various degrees of pollution vulnerability. The obtained results show that: i) the high˗vulnerability zones extend over the entire free part of the lower ground˗water (in the South of the aquifer), and ii) These zones lack natural protection of the ground˗water. Precisely, the pollution vulnerability becomes very high in the southeast part of the studied sector, mostly in the quarry areas where the exploited biosandstones play the reloading role with respect to the lower ground˗water. The zone with moderate vulnerability extends over the north part, where the ground˗water is covered by the upper, and the middle, fine˗grained to marly lithological formations. In the same zone, the vulnerability becomes low at the level of wetlands. As a conclusion, it is important to carry out strict control and follow˗up of the ground˗water to optimize its role as a strategic reserve in the Tangier’s region.

Keywords: DRASTIC model, groundwater, vulnerability mapping

References

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