When the Restricted Data contained in material is not ascertainable by observation or examination at the place where the material is located and when the material is not readily removable because of size, weight, radioactivity, or similar factors, DOE may authorize the permittee to provide such lesser protection than is otherwise required by §§ 1016.21 to 1016.23 inclusive, as DOE determines to be commensurate with the difficulty of removing the material.