The phrase "smoldering pile" refers to a large amount of burning material that is emitting smoke and heat but not bursting into flames. Full definition
But that's what happened, as Okrepkie received word that his house had been reduced to a smoldering pile of embers. (relevantmagazine.com)
Another flung a beautiful gown and a rich cloak onto the smoldering pile. (religion-online.org)
The levels of dioxin measured in the air near the smoldering pile «were the highest ambient measurements of dioxin ever recorded anywhere in the world,» levels at least 100 times higher than those found downwind of a garbage incinerator, according to an analysis published by EPA scientists [pdf] in 2007. (scientificamerican.com)