Can fly ash be used for back filling of open cast mines?
Ans. Yes fly is a good material for back filling of open cast mines. It can be used as a structural fill material that is by laying in layers and with appropriate compaction. It can also be used alongwith overburden with intermittent mixing i.e. if 10 dumpers are bringing over burden, two dumpers can be employed bring in fly ash and all these materials can be backfilled in a regular manner as per the existing practice of back filling. The fly ash would get automatically intermixed and fill up the voids in the over burden material, providing it stability and nutrition as well as water holding capacity for aforestation.
