Wow, I have no advice on how to really handle that, but all I can say is on warm days, it's really nice to have place to take a cool dip.
Ours is just a little above ground, but it really takes the edge off on the warmest days of summer.
That being said, on some of the sites I've visited on pool maintenance, I believe it's possible to clean that up, but it would be a lot of work no matter if you emptied it, or nuked it and filtered it. I know my next door neighbors pool looked like that after they left, but the current owners have it cleaned up and are using it, and I don't think the drained and refilled.
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If all your friends are exactly like you, What an un-interesting life it must be.
"A door is what a dog is perpetually on the wrong side of" Ogden Nash