Help !.. I have now gained access to a basement that hasn't been cleaned or cared for in 15 years. There is a tremendous amount of soot, dirt and dust on the cement floor. I have swept, mopped and scrubbed to no avail. It cleans for the moment and leaves streaks of dirt all over the floor when dried. I would like to paint the floor but cannot paint over the filth.Is there any way to eliminate the dirt? Any help is greatly appreciated.