I agree that the site should be abandoned. Was describing my idea of how to most quiclky drain it, and not making a judgement regarding the wisdom of re-occupation/
They should save what is on high ground, build a double or triple wall to protect it and then let the remainder go back to wetlands.
Even letting the area "go back to wetlands" will require nearly unimaginable amounts of time and resources. Just three words to explain what I mean-----Environmental Impact Study.