GAL does not owe back taxes as far as I know so you can't foreclose on them. You can however take the property by Public Domain and pay the landowner a fair value. Cities and States used to do this to build highways and hospitals -things for the common good- but in recent years have done so then sold the property to developers.
In Port Chester they did it when 1 landowner was holding up a large development about 10 years ago and recently, I think in New London or Groton Ct. property was taken for a residential development. I do not agree with it for private projects, but I'll make an exception when it's good for my team.
NYC is different in that someone who rents a property can hold up development by a property owner because it may spoil his view.
I'm pretty sure you mean eminent domain. That sounds a lot better.