Abstract: Apparatus and method for impregnating and sealing and simultaneously improving the tensile strength of pipeline or conduit buried in the ground. The structure consists of a pair of axially spaced, deformable blocking and sealing devices whose interval is appropriately maintained. One of the blocking devices or "pigs" conveys conduit for introducing air under pressure greater than surrounding hydrostatic pressure on the conduit exterior to the space between the blocking devices to force out water or contaminants and also means for introducing two parts of a compound to impregnate, seal and bond to the interior conduit surface. The structure is also provided with a camera chip on the "pig" which contains the structure for conveying the air and the parts of the compound for observation by remote camera of the operation. The compound is a fast drying compound enabling relatively continuous operation by winching the structure along the conduit.