There is provided a sealing assembly for a bearing assembly that supports a rotating tubing string that extends through the riser. The sealing assembly has a plurality of sealing elements. Each sealing element has a seal body having an inner sealing surface designed to seal against a tubular body. The sealing assembly also has one or more sleeves that removably attach between adjacent sealing elements. Adjacent sealing elements are attached to the one or more sleeves in axial alignment. A chamber is formed by the adjacent sealing elements and the corresponding sleeve. The sealing assembly further has a bearing attachment for attaching the plurality of modular sealing elements to a rotating portion of the bearing assembly such that the sealing elements extend downward in series from the bearing assembly and rotate with the rotating tubing string.