Tricia, by chance does this 2 ft. hole lead under another part of the house which does not have basement under it? If so, this is a crawlspace access, and should have a cover or door put on it, but not permanently sealed over. This is true whether the hole is square, or a broken out looking hole; sometimes the access was put in after the walls were done, either because it was forgotten, or that it leads to a crawlspace of a later addition.