METHOD TO RECOVER ABANDONED PITS Russian patent published in 2012 - IPC E21C41/32 

FIELD: mining.

SUBSTANCE: method includes separate excavation, movement and storage of the soil layer and overburden rocks, mining of the open-pit field, filling of the mined space to the border of the upper level of ground water with construction wastes close in their composition to natural minerals, laying of the draining layer from construction wastes, with thickness of at least 0.6 m and fraction size of 150-200 mm. After filling of the pit with construction wastes, terracing is carried out using a bulldoser, at the same time at first the site is laid out, and furrows that mark borders of future terraces, paths and access roads are tilled. Then the bed of each terrace is formed serially with the bulldoser with a reverse cross inclination up to two degrees, along the entire perimetre of the pit. Bed width at each terrace is arranged as at least equal to seven metres. Then retaining walls are arranged from plates or stones and are bound with cement mortar. The drainage system is laid, and places are arranged on the terraces for burial of the deceased.

EFFECT: reduced labour inputs and cost of recovery works.

1 dwg