In Estonia, Tônis Meriste, director of development at
The mixture of shale ash with bitumen and crushed asphalt could replace granite gravel in laying the sub-base in road building.
However, in Estonia, shale-oil fired power plants' shale oil ash is classified as hazardous ash and is subjected to pollution tax.
Meriste says other countries, including Germany, US, Holland and Finland, classify fossil fuels power plants' ash as a raw material used in cement production, in road building, re-cultivation of idle excavation areas.
Eesti Energia's power plants' shale ash is supplied to Kunda Nordic Tsement for the production of Portland cement (shale ash content 30%).