Abstract: A tool and method for splitting an existing underground polymeric pipe into a plurality of strips and for expanding the strips and the surrounding ground to permit replacement of the existing polymeric pipe along its length from an entry excavation to an exit excavation without excavating entirely along the length. The tool includes a nose sized smaller than a minimum inside diameter of the existing polymeric pipe, a blade unit attached to the nose having a plurality of cutting blades extending therefrom radially outward about an imaginary central axis, each of the plurality of cutting blades having a forward opened "V" shaped cutting edge sized larger than a maximum outside diameter of the existing polymeric pipe for cutting the existing polymeric pipe into strips along the length thereof.