native american burial mound?

OK so I just found out this public place is built on top of a burial mound… there are still bones in it and the bones they already dug up were reburied in another location in a mass gave type deal…. is this right? it has been kind of bothering me since I found out about it…. but does this happen alot at old burial sites? shouldn’t they have moved all the bones/artifacts first? or is the fact they left it alone ( and built on top of it) better? OR should they have not been allowed to build on the site at all? thoughts? opinions?

thanks!
this place was built in the 40’s and continued expanding through the 70’s…. and a certain television station owned it and basicallyl covered up the fact it was such an extensive site… I think it was pretty illegal actually…. but I mean what can be done now? the damage is done… however, I still feel horrible about the fact there are still people burried there…