1.1 ,The practice describes the procedures for the rehabilitation of gravity pipes, culverts, tunnels, and conduits by the installation of a field-fabricated PVC liner system. After installation of the liner system, cementitious grout is pumped into the annular space between the liner and the host structure. The rehabilitation of the host structure by this installation practice results in a rigid composite structure (PVC liner/grout/existing pipe). This type of rehabilitation process is suitable for a variety of gravity pipe applications such as storm sewers, sanitary sewers, and culverts, and with geometries including circular, egg, ovoid, elliptical, arch, and site-specific composite shapes.