I have a waste pipe in the floor that goes to somewhere , not sure exactly as it just disapears into the groud, we have the dish washer and washing machine waste pipes in it, every now and then we get a really bad rotten eggs smell in the house that we think may originate from that pipe ( not 100% sure) can anyone tell me what it could be etc???
It sounds like you are draining into a line with no trap, and sewer gas is being allowed to escape. This is a very dangerous condition and you should call a plumber to take a look at it.