On the relation between gas production of wastes, repository layout and environmental consequences of disposal

The formation of gases in wastes is a common, often well described process, that is in some cases even used for commercial energy production in gas fired power plants. On the other hand, this process may cause severe problems, since most of the gases are burnable or even explosive and sometimes toxic. If considering deep underground disposal of hazardous wastes gas formation may further be a concern, as the system of engineered and natural barriers may be jeopardized by pressure build-up and, in consequence, disruptive events that provide release pathes for the gaseous or dissolved residues of the wastes. The paper deals with possibilities to cope with this problems as far as related to the operating period of a repository in the deep underground and with environmental consequences in terms of release of hazardous material with the exhaust air of the disposal facility. (au)