This still reads like a failure of governance to me.
It’s up to Chemours whether to hold themselves responsible for not meeting their internal guidelines (from what I read here they did/do). Of course it’s less than ideal they keep everything silent but their incentives probably point them that way.
If the government also knew, and chose not to do anything (and indeed, apparently wrote that it’s not financially feasible), then that’s a fault of government. The company won’t close itself if what they’re doing is morally dubious but legally perfectly fine (especially the people working at that location have a great incentive to not make waves, even if they’re the ones drinking the water).