“…Secondly, since landfilling is the most recurring MSW disposal option in South America, the use of mechanical-biological pre-treatment could have a great impact in terms of reducing the needed sanitary landfill volume (Adani et al, 2004;Fehr, 2003;Mbuligwe et al, 2002), reducing the gaseous and liquid Table 1 MSW average composition (% ww ) in different countries of South America (Acurio et al, 1998) Acurio et al, 1998). emissions during the landfill operation (Bockreis and Steinberg, 2005;Mü nnich et al, 2003;Robinson et al, 2005;Zach et al, 2000), and enhancing the waste body stability, which can result in significant advantages in the aftercare phase of the sanitary landfill (Stegmann et al, 2002). In addition, although the operational costs of implemented MBT facilities are not fully available to the public, except for studies that resulted in 30-60 EUR per metric ton (t) of treated wastes (highly depending on the size of the MBT facility), the reduction of the long-term operational and aftercare costs of the sanitary landfill, as well as the possibility to obtain reusable and/or recyclable material streams as by-products, can overcome the costs of MBT in comparison with the operational costs of a sanitary landfill for untreated wastes (Seifermann, 2002;Rodríguez-Iglesias et al, 2003;Fricke et al, 2002).…”