I notice the other day that our basement floor has 3 or 4 eight inch square holes in the floor. Most have some type of drainage pipe running through that has been cut (3 or 4 inch cast iron). How can I plug these up? We want to remodel the basement and these holes are in the middle of the floor. Also the basement does have a sump pump that one of these 'drains' leads to. Would I be better off cutting up the basement floor and replace all of these drains? How else would we fix these?