RECOVERY METHOD OF MINED-OUT PITS FOR CONSTRUCTION OF CEMETERY Russian patent published in 2017 - IPC E21C41/32 

FIELD: mining.

SUBSTANCE: invention relates to the technical recultivation of mining pits remaining after the excavation of building stone and other subsurface minerals. The method includes separate excavation, movement and storage of the soil layer and overburden rocks to the seperate belt-type dumps, 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 with fractions of various size, layer by layer with further compaction of each layer, laying of drainage layer with construction waste with fraction size of 150-200 mm. An intermediate layer is laid on top of the drainage layer with construction waste with fraction size of no more than 120 mm until its upper boundary reaches 1/2 of the height of a pit mined space. Initial pit mined space infilling is performed on top of the intermediate layer with an equivalent mixture of overburden rocks, clay and construction waste scrap with fraction size of no more than 100 mm, wherein the infilling is performed layer by layer with thickness of every next layer of no more than 1m and with compaction of each layer until the complete filling of the pit mined space. Then the whole surface is levelled by a bulldozer. The pit mined space infiliing is performed on top of already levelled by a bulldozer surface with an equivalent mixture of sand and gravel of fraction 5 with layer thickness of no less than 100 mm and with further planarization.

EFFECT: invention provides reducing labour costs of recovery work.