I wouldn't call it a sinkhole, so much as a washout,....but that's a small beer at this point.
The point being is that the WEIGHT of the missing strata is what HOLDS the grout curtain and sub wall in place against the forces being applied on the lake side.
a shisttitic formation capped with schidty engineering.
GTC
Member, Clan of the Border Rats -- “Sometimes I wonder whether the world is being run by smart people who are putting us on or by imbeciles who really mean it.”- Mark Twain
