It was the year 2006 anyone not buying real estate was considered a fool. 

I was the mortgage broker for a buy and hold investor that ventured into a drug-infested neighborhood and purchased two homes for $145,000 each, the pig's wearing lipstick. Bold rehabbers had supposedly turned the community around. 

What they did not mention was that they kept guard day and night in order to keep copper wiring and plumbing from vanishing before the big payday from the flip. Every home received a new A/C compressor the day before closing and not a minute sooner. OK OK you get the picture.

Tenant left and days later the new A/C unit, plumbing, and wiring also went.

It's 11 years later, the bank has not received a payment in 8 years, they have written off the debt and no longer reports the negative payment history to the credit bureaus BUT the city of Atlanta expects payment for taxes and general upkeep of the yard.

Can a quiet title action be a remedy so that he can dispose of these properties?

Not likely......a QT is not intended to remove a legit mtg.

Any thoughts, the house needs to be torn down and now the neighborhood is starting to evolve back into a place worth living in.

You can try to sell them for what is owed. You could look at doing owner financing and apply the down payment towards what is owed in taxes. You could leave the title issues in place and let the new owner quiet the title.  Otherwise you could reconnect wires and switch to pex which might not cost that much and then rent them out. I would interview property managers that could get estimates from their contractors and go with the property manager that gives the best estimate and deals regularly in this neighborhood. Otherwise city will probably demo the homes and stick owner with the bill.

Quiet Title can be used to eliminate the written off mortgage. It's being done regularly in our area. Check first though, I've found multiple properties where the bank had already released the mortgage, and the owner didn't know.

Taxes are a county level issue, and there may or may not be a way to work with those.