Abstract: According to the national environmental report of 2010, the amount of waste generated from construction and demolition activities is around 1 million tons every year and still rising. Most of the time, construction and demolition waste end up in landfills mixed with the domestic waste or used to fill an old extraction field of natural aggregates while they can be put to use at the moment of closing landfills and more specially in draining the biogas. To evaluate that possibility, this study comes to compare the draining process based on natural aggregates through the literature with the one based on recycled aggregates from C&D waste, environmentally and economically. And how the recycled aggregates may react to the aggressive chemical composition of the biogas that may influence the draining process. Also the fact that mixing the C&D waste with the domestic waste causes automatically a differential settlement of the waste inflecting an enormous loss in the sealing of the landfill permitting the leak of the biogas to the air.