Abstract: An elongated containment tube is formed to serve as a retaining means during high-pressure compaction of ash resulting from cremation of humans and animals, and thereafter as an extended service life containment system for interment. In preferred embodiments, the containment tube may be made of various impervious metals, plastics, or ceramics, and employs one or more end caps having a range of sealing means that ensure high-integrity retention of its contents. End cap sealing means, such as circumferential deformable/deforming teeth and compression rings, are employed, and the long-term and stable burial of a large number of individual containment tubes in a single, conventionally sized grave plot is described.