To reduce disposal costs by suppressing the amount of capital investment due to the small-scale development in response to the natural environment by a method for separately constructing a dedicated disposal site from a final disposal site for the purpose of achieving the simplification of the disposal site and of realizing the reduction in disposal costs by detoxifying and stably solidifying only harmful inorganic particulate waste inside the disposal site in order to reduce the environmental load to the disposal site in a present condition that remainder of the final disposal site is tight, and to make residents easily obtain understanding and reliability for the construction of the final disposal site of the next-generation by contributing to the prolongation of the life of the final disposal site and future environment conservation.

The detoxified waste is transported and packed in the disposal site as fluid mortar to be condensed and solidified. As a result, the pressure to a water shielding wall in the dedicated disposal site is almost equal to zero, thereby facilitating the structure of the wall. Under the construction, a temporary awning for preventing rain water from intruding is necessary, thereby becoming a constitution completely separated from the present final disposal site.