thank you. As for ‘irreparable’ damage. Basalt rock is even harder than granite, if I remember my college geology course correctly, thus not much to repair other than the soot to wash off. And the rain will take care of that over a few years.
[snip] All but 53 of the more than 900 moai known to date were carved from tuff (a compressed volcanic ash) from Rano Raraku, where 394 moai in varying states of completion are still visible today. There are also 13 moai carved from basalt, 22 from trachyte and 17 from fragile red scoria. [/snip]
https://en.wikipedia.org/wiki/Moai