Methodology for determining impacts on the chemical status of groundwater bodies: An application in a Mediterranean river basin (Southern Spain)

Abstract

In this paper a practical interpretation of the criteria established in the European Water Framework Directive to evaluate the impacts on the groundwater chemical status is carried out by means of physicochemical parameters and related threshold values. As a result 67 parameters have been identified to evaluate the chemical status of groundwater, and the threshold values for each of them have been proposed. Groundwater bodies designated as protected areas having a special use have also been taken into account. These include groundwater bodies used for the abstraction of drinking water and groundwater bodies designated as nitrate vulnerable zones. The proposed procedure has been applied in a pilot Mediterranean river basin located in southern Spain. Results show that groundwater bodies in aquifers with intergranular porosity in general have important impacts on their chemical status, whereas those identified in carbonate aquifers have a good chemical status. The main pollutants are: nitrogen and phosphorus compounds (related to agricultural practices), hydrocarbons and metals.