[freebeard]

I'm concerned about growing hills of Spent Shale: https://en.wikipedia.org/wiki/Oil_shale_coke

Depending on the extraction process and the amount of remaining organic matter, spent shale may be classified as oil shale coke, semi-coke or coke-ash residue, known also as oil shale ash.[1][2] According to the European Union waste list all these types of spent shale are classified as hazardous waste.