I have a kitchen sink backing up because of a bad galvanized pipe that goes under the concrete floor in the basement. Can I cap off the galvanized pipe that comes out of the basement floor about two feet and then run a new line through the cinder block in the basement, then go outside with the pipe and t into the sewer line. I don't want to cut up the basement floor. The cider block that I would like to cut through is about three feet under ground