ABSTRACT
An overview is given of the presence of atrazin in the recharge system of the Dune Water Company of South Holland (DZH). The infiltrated load per annum of atrazin was at its highest in 1990 (10 kg) and decreased to 1–2 kg in 1997. In the conventional surface infiltration system, which is only slightly anaerobic, approximately 50% of the atrazin is removed during dune passage, while in the highly anaerobic well-recharge system of Waalsdorp, over 90% of the atrazin is removed from the infiltrated water. In order to improve taste, odour and colour and to further reduce the remaining concentrations of pesticides, activated carbon is added as part of the posttreatment for the production of drinking water.
An important question remains as to whether atrazin break-down products are still present in drinking water but cannot be detected by the techniques currently in use, or whether break-down products adsorb on soil particles.
