First I need for you to tell me how many people live on reclaimed dump sites.
As for the "forseeable" future, I do keep in mind that I have children who, God willing, will one day have children of their own who, God wiling, will have children of their own, etc. I don't see the population of the US shrinking drastically in the forseeable future, if it declines at all. More people, more trash. More landfills, less land available for living. So what if I recycle? Its not like I'm doing a bad thing, and I'm not wagging my finger at those who choose not to recycle. But I don't for a second believe that landfills can be safely reclaimed.
As for unwanted babies and mobsters, they are dead, or soon dead, once they hit the dumpster or landfill. They didn't die from living there and nobody claimed that they did. I bet their life expectancy would be drastically reduced, however, if that's where they were living.
If I knew I would tell you. In the world the number is undoubtedly thousands. The question was rhetorical really. The point I was trying to make is the mechanism for a dump to cause any harm to the blessed environment or humankind has never been shown. They have polluted water in the old days and that can cause health problems, but today that's a non-issue.
Dumps are unsightly when operating but innocuous when closed, except they will break wind occasionally like a big herd of cows if they aren't plumbed to collect the methane.
Your grandchildren and mine won't be bothered by our old trash. They'll have bigger problems to deal with I'm sure.
"More landfills, less land available for living."
More landfills, more land available for parks, which make live worth living.